A heavily indebted car mechanic in Cambridge who found £193,000 in his account – following a sort code error by a pensioner – says he thought the money was from his “nan’s estate” and that Barclays initially refused to take the money back.

The Guardian revealed last week how fellow Cambridge resident Peter Teich, 74, lost his £193,000 inheritance after he gave his solicitor the correct account number, but made a simple error on the sort code. Barclays told him the recipient had refused to give permission for the money to be returned, leaving Teich to mount an expensive legal battle to recover the money.

But Tim Gray, who received the money, sets out a different version of events. “The main thing is that I didn’t spend the money, I didn’t run off and buy a Ferrari, and I did try to give it back.”

Gray, 42, said he was at work on a Friday afternoon when he checked his bank balance on his phone and saw the £193,000 credit. “I thought, whoa, bloody hell, whoopee. I could see it was from a solicitor, a Chaps payment, so it had obviously been checked. My nan died three years ago and I thought, what’s going on here, it’s the same place and address where my nan’s solicitors were, so I thought that was it.”

Later than night, Gray paid off his his outstanding credit cards and bills, leaving about £155,000-£160,000 in his account. “I know it sounds like a life-changing amount of money, but it’s not. I’m in debt to more than double that amount. I thought it was my money, a couple of friends said it must be my money, and I only spent a bit of it.”

Four days later, on the Tuesday lunchtime, he received a text from Barclays, asking him to call.

“He was a lovely guy at Barclays. He said that’s not my money. I said take all the remaining money, but leave me with the money I’ve spent. But they said they wouldn’t take it. I said take it back, but he said no, and that his hands were tied. They said they would put my account on hold, but I said no, I need it for work.”

Barclays disputes Gray’s version of events. In a statement, the bank said: “We have reviewed our contemporaneous record of the telephone conversation and it does not reflect the claims being made on this case.”

After the call with Barclays, Gray says “many weeks passed” without anything happening.

“I didn’t want someone else’s money in my account and I was worried about spending the money so I transferred £150,000 of it into premium bonds.

“I thought if I won a lot, then I would make some money and whoever the money belonged to would get their money back anyway. But I only won a few small premium bond prizes.”

At no point, says Gray, did he know the money belonged to Teich, or that it was his inheritance.

“Barclays knew everything about me, but I knew nothing about him, not a whisper. I didn’t even know if the money was from a company or an individual. The first I knew his name was when someone came knocking at my door at 8pm one evening, serving me with a summons, and the next day I was in court in London.”

Teich had instigated legal proceedings himself and after the court ordered Gray to repay the total amount he borrowed money again on his credit cards, cashed in the premium bonds and the £193,000 was returned to Teich.

“I’m glad he’s got his money back. I feel sorry for the old boy, it should never have happened to him. I just want to clear my name. I’ve got a couple of kids and we’ve had reporters knocking on my door. They don’t leave you alone.”

But Gray says that while his partner has felt bruised by the experience – “she thought people might think we are common thieves or that she might lose her job” – to him it has been a bit of an adventure.

“The whole saga has been a mix of excitement and worry. There have been times I haven’t been able to sleep. But then I’ve got one hell of a story to tell my grandkids.”

Astonishingly, he reveals that it’s not the first time money has wrongly landed in his account. “It’s actually the third time this has happened to me,” he says, although never quite £193,000.