We’re at our wits’ end with John Lewis Finance after it turned down our credit card claim.

Last year we paid a small independent company to supply and install a kitchen for us. The total cost under the contract was £29,950. We paid just under £9,000, mostly on credit cards with John Lewis Finance. About six months later, when the installation date was approaching, we paid the same company for the purchase of kitchen appliances – but under a separate contract.

Unfortunately, the company then effectively disappeared, and all our attempts to contact them have failed. So we took the matter up with John Lewis as our credit card provider. First, the staff refused to charge back, without explaining why. Then they said they wouldn’t refund us under section 75, because our contract (singular) was for more than the £30,000 upper limit. We have sent them the two separate contracts, with as much information as their online form allowed, but they don’t seem to understand that the contracts are separate and should have been treated as such.

We have phoned them three times in the last month to complain but have been told our case is hopeless because of the £30,000 limit, and we should just drop it.

This whole experience has been very distressing for us, and John Lewis’s refusal to engage at all leaves us at a loss now as to what to do next. Can you help?

JH, West Sussex

This is not the first letter we have had from a reader who had had what appeared to be a perfectly valid section 75 claim turned down. The clause holds credit card providers jointly responsible for providing the item or service bought via the card, provided it costs at least £100 and below £30,000. Consumers can claim from the card provider if the supplier collapses before the contract is fulfilled, provided the payment was made directly to the company in question. You don’t need to have paid the full sum to claim, just at least £ 100.

However, as Guardian Money has reported in the past, banks are often very reluctant to pay out such claims.

At the time of your payments, John Lewis’s credit cards were provided by HSBC – since switched to New Day.

As a result of our intervention, the bank has now agreed to pay your claim near £30,000. An HSBC spokesperson said your claim had been “incorrectly assessed by our agent”. It has also apologized and sent you a further £200 goodwill payment.

Audi dealer repairs

There was a very interesting response to our recent request for readers’ experience of using Audi dealers for repairs to older cars. Some of the reports were shocking.

KM described taking his 10-year-old Audi Q3 for a service and MOT at a main dealer.

“It failed the MOT due to two damaged tires and a broken rear suspension spring. In addition, the dealer recommended the replacement of brake discs, repair of an oil seal and a transmission fluid leak, and replacement of a cam belt, even though this was not a requirement in the car’s original service manual. The total estimate to be paid for the ‘required’ work was about £6,000.

“I took the car to another garage, where most of the work was deemed unnecessary. They found no evidence of leaks, the discs were fine, the rear brake pads were replaced (although there was plenty of wear still left on them) and the broken springs were replaced. The total cost for this, including two top-quality tires and a repeat MOT, was £734.”

AW wrote: “My Audi A5 was in our local dealership for an annual service and its first MOT. Unfortunately, the MOT failed as the ‘offside rear shock absorber had a serious fluid leak’. The helpful inspection video on the dealership customer portal showed the oil trickling out. The cost of replacement was enormous, especially as the recommendation is to replace both sides at the same time.

“I rang a friend in the trade to get a cheaper quote. He expressed huge skepticism. The dealership reluctantly released the car, saying it wasn’t legal to drive. I took it straight round to another MOT station (not mentioning its recent fail) and it passed with no issues. And six years on, there’s still no sign of a problem with the shock absorbers.”

PC wrote: “About 10 years ago, the driver’s airbag warning light on our nine-year-old A4 came on. The dealership wanted £250 to run a diagnosis, and advised that subject to that, it was likely an airbag failure, which would cost £2,500 to fix.

“A quick Google suggested that in that model, with electric seats, it was not uncommon for the electrical connection under the seat to work loose with time. For £25 I bought a bona fide VAG code reader online, and read the diagnostics for myself. I checked the connector, pushed it tight and reset the error code, and it was all fine for the rest of the car’s life.” Caveat emptor.