MoneySavingExpert Martin Lewis has warned bank customers not to throw away a letter appearing to be from their provider.
Anyone with an HSBC, First Direct and M&S account could receive an unexpected cheque in the post.
However, some people have thrown the letter away thinking it's a scam - but it's not.
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Martin wrote on Twitter: "WARNING: Are you/were you a customer of HSBC, First Direct, M&S or John Lewis finance?
"If so keep an eye on your mail, you may be sent a cheque, it isn't a scam, one man nearly chucked it."
Last week, the finance guru explained on The Martin Lewis Money Show why customers are receiving the £50 cheque.
He said: "This is really important for lots of people.
"If you banked with HSBC, First Direct, M&S Bank, and John Lewis Finance between 2010 and 2019, and you were in arrears at some point on one of their debt products - mortgage, credit cards, loans and others.
"It admits its customer service was wrong, and so it's automatically sending out compensation."
Martin added: "People are going to get these letters up until March.
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"If you think you are due one and you don't get one, I'd get in touch.
"But watch out for these, do not bin them, these are cash in the bank, put the cheque in."
