Chat GPT got me a new mattress — but should you use it to write your consumer complaints? 

Five minutes on Chat GPT got me a brand-new mattress for free — but here’s where you need to be careful

Whether we like it or not, AI is now increasingly part of our lives, with a lot of companies now incorporating it into their products. My security cameras can now tell which dog walked into view, and just last week, I noticed that my sister’s washing machine has an “AI” button (I’m yet to discover what it does!). 

But it’s not just a tool to upsell us to a new TV, or let big business cut staff — used right, AI can give you a fighting chance against large corporations with huge legal teams. And it can go some way to reduce some of the faff we deal with daily too. 

During one sleepless night on our mattress that I was sure had a slant, I chucked the details into Chat GPT to ask my rights and see if I had grounds for a complaint. Then I got it to write the complaint for me. The following morning, I gave the email a quick edit and sent it, along with photos, to Emma. With only five minutes (if that) of work, Emma has agreed to replace the five-year old mattress free of charge, and is even upgrading the model. 

These tools can be really helpful when pulling together information and making sure you’re covering all bases. It can also help to understand your rights and can rewrite your text to remove emotion or harsh language, but should it be used in the first instance? And will it get you the best response? 

Here’s how to use AI to help you write a complaint, and what you need to be careful about. 

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How AI chatbots work

In short, AI chatbots like Chat GPT, Gemini and Claude are trained using vast amounts of data, including websites, books and articles. They learn patterns and language structures. LLMs (Large Language Models) use this learned information to generate responses.

They don’t necessarily understand what they read, but they’ve learnt what “correct” looks like, and then use that information to generate new text that fits the model they’ve learnt.

So if you ask them for a complaint letter, they look at similar cases that exist and pull in the parts they need to make your version as close as possible to the “ideal” version of a complaint.

However, they’re governed by what you ask them. So if you ask for an angry complaint letter, they will try to find a way to do that. If you ask for a technical one, they will remove any trace of emotion.

Worryingly, they also don’t just pull from existing information when generating something for you. To satisfy your request, they sometimes simply invent facts or information because that would make the result fit better with their version of “correct”.

But the fact they understand plain language and have consumed a truly vast amount of information means they can be used very effectively for research on practically any topic – just be careful to check what sources they’re pulling from before relying on what they tell you.

They are also excellent at structuring written English, whether formal or informal, so can be useful to polish writing or check for errors or mistakes.

Should you write a complaint with AI?

I spoke to Martyn James, a consumer finance expert, who weighed in on using ChatGPT, Claude and Gemini to write your complaints for you. Here’s his take:

“There’s an old adage about making a complaint using legalese. If you write a legal complaint, you’ll get a lawyer’s response. 

“The point of this is that quoting clever bits of law means you’ll get a legalistic response which overlooks the human impact of a complaint. The dangers of using AI are the same.

“In many ways, complaints should be made in your own words because every complaint is unique and should reflect the impact on you as an individual. The danger of using AI is the business will miss key nuances that personalise the complaint – like the impact on you personally. AI may also extrapolate using facts that aren’t relevant, which can make it look like you are making things up. 

“Another risk with AI is the ‘job application’ factor. If I say to AI, ‘write me a car finance complaint’. It’ll do a standard job. But if everyone is asking ChatGPT to do the same thing, then there will be thousands of identikit complaints going in. When that happens, firms use template letters to respond to them all – in other words you get a very binary, black and white service. When claims managers took over PPI complaints, I used to see thousands of the damn things and they ALL followed the same pattern. Not one explained the circumstances that lead up to PPI being taken out, and many, many people lost their complaints as a result.

“But when used to accentuate a complaint, AI can be brilliant. For a start, rather than using it to improve your grammar and wordsmanship, you can ask it if you have missed out any important information. You can use it to write up a timeline of events in bullet points. You can write a long draft and it can cut out any repetition. You can ask it to tone down any rude or aggressive bits that might have slipped in too.

“In addition, you can use AI for research. If I’m complaining about potholes, I can ask AI to find references to that specific pothole from the web. This will give me evidence I can use to support my claim. Insurance T&Cs overwhelming? I can feed them into AI and ask them to identify anything that relates to my claim – that way I can argue if the clauses are too hidden, unclear or vague. 

“So as with using AI in anything, use it to get started, then personalise, or write your own complaint and use it to make it easier to understand. Oh and AI works well for research too, but you’ll need to check the sources.”

When not to use AI to write a complaint

It’s probably easiest to avoid using AI or Chat GPT in the first instance. I admit, I didn’t follow my own advice here. I dove straight in with my email to Emma — but I was quite sleep deprived. Try approaching the company with your initial and honest thoughts, explain what went wrong, how they can improve and what you want out of it. 

Stick to the facts and try not to get too emotional. Smaller companies or those with excellent customer service should respond well to your feedback and you shouldn’t need to take things much further. 

This keeps it “human” — you’re expressing how something has impacted you as an individual. You can use the tool to tell you about any gaps or have it rephrase any waffle, but for the most part, it should sound like you. 

When to use AI to help write a complaint

If that doesn’t work out, it’s time to write something a little more formal. This is where you want a well worded complaint that covers everything in a structured way, and makes it clear that you know your rights and mean business. It also lets the company know how it can resolve the issue. 

Start by pulling together a summary of everything – this can be as much waffle as you want or it can simply be bullet points of the facts. If you’re dealing with a bad service, like a delayed flight, it can be a good use of your time while you wait. At this stage, keep out personal details like your name or any identification numbers. These can be added in later. 

Make sure you include:

• How you purchased the product – you can be specific about the company you bought it from, in this case, it may pull specific information from their website; or, if it’s a service, rather than a product, list out exactly what happened in chronological order
• What went wrong – go into detail here, the AI tool will pull the relevant information
• Details of how you’ve contacted the company already — if you’ve already been in contact with someone about the problem, explain the details
• What you want out of it — do you want a refund? An apology? A replacement? Being clear here can really speed things along

For example, I sent the below list to Chat GPT and asked it to help me write a complaint for a completely fictional issue with a washing machine. By including the retailer, it pulled specific information from the Currys website. 

• Washing machine bought 6 months ago from Currys
• Installed by company
• Now doesn’t fully drain
• Spin cycle results in an error
• Have tried contacting the store but they’re refusing to take responsibility for the problem 
• Want a new washing machine  
• Needs to be collected and a new one delivered

Here’s the drafted email. The key thing is, don’t send it exactly how it is — change the text to make it more specific to your situation and ensure that it still sounds human. You also need to ensure that it’s correct and not quoting from completely bogus laws. So if it mentions a precedent or a law, check online to make sure it’s real.

Make sure that you talk about how you’re impacted — if it’s a faulty mattress, mention the lack of sleep or back pain that it caused. If it’s a faulty washing machine, as below, mention the laundry that’s piling up while you wait for a resolution. 

Here’s Chat GPT’s email and how I would edit it:

What Chat GPT got wrong

There were a couple of things Chat GPT got wrong in its response here. Firstly, it completely left out the concept of a repair in the resolution – this is likely because I wrote in my prompt that I wanted a replacement, but just because you want a certain resolution, it doesn’t mean they have to give you that. I added a line to say that I wanted either a repair or a replacement.

Secondly, Chat GPT included chargeback as one of the ways I might escalate the problem further — you can only do this within 120 days, so this is too late for a chargeback. In addition, if I hadn’t paid via a credit card in this (made up) example, I wouldn’t be able to use Section 75 either — I made no reference to how I paid in my prompt, so Chat GPT filled in the gaps.

You can see exactly how this happened when you think about how generative AI works. Both of those solutions are valid in a lot of situations, so when looking at a lot of possible complaint letters and consumer guides about complaining, they feature a lot of the time. They are part of the “ideal” complaint as it understands one to be. However, because the chatbot doesn’t understand what they mean in the real world, it included them even though they don’t work here.  

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What you need to consider

Firstly, remember that AI tools pull information from several sources across the internet, rarely understand sarcasm or satire and they’re not always right — they’re often terrible at solving anagrams, can sometimes make up facts and fill in details that aren’t clear with nonsense. This final point is where you need to be really careful. 

Before you begin, check that you definitely have a valid complaint — research the situation, see if anyone has similar problems with the company or product that you’re complaining about. You can try asking the AI tool directly if you’re unsure, but you need to fact-check the response. 

Sometimes, the more detail you give, the better the answer will be. If you specify the problem you’re having with a product, you might be able to find sources that prove that it’s a known problem and not a one-off incident. And specific company information means that warranty and guarantee information can be taken straight from the website. 

Chat GPT is also a bit of a cheerleader — I tried telling it that I wanted to throw a dinosaur themed birthday party for my pet llama and instead of saying “that’s ridiculous, Zoe”, it told me it was “objectively delightful” and planned everything, including food, activities and party favours. The point is, that it tends to be on your side, so while it can give you a reality check and make you realise that you don’t exactly have a leg to stand on, you have to read between the lines a bit to determine if you actually have a case. Someone recently described it to me as “a super enthusiastic friend who knows everything but has zero common sense or real-world experience”, and that summed it up brilliantly for me. The good news is that it can give you some good reading to figure it out, and if you prompt it correctly, it might give you a more honest answer.

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Summary: does Chat GPT write good complaints?

In short, yes. The complaints that Chat GPT writes will generally do the job, but they might be a little too formal. Whenever I’ve used it, I’ve always taken the key points but adapted the copy to make it a little bit more natural. 

But in reality, there’s nothing wrong with using AI tools to help you research and form a complaint. At the end of the day, large companies have entire legal teams, so having access to a tool that can quote the laws they have to abide by can help you even out the playing field. Just make sure you keep your complaint human and share how you’ve been impacted personally. And fact check everything that it adds — you’re not going to get anywhere with AI-generated laws. 

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