Some tens of thousands of people woke up on Christmas Day to doubled wages and a higher-than-expected bank balance after Santander did an oopsie, depositing £130 million ($176 million) into accounts held by its UK customers. Santander would now like the money back, please.

The deposit mishap was the result of a mysterious “scheduling issue,” according to The Times, which first reported the story. The bank confirmed to The Verge that some payments were accidentally doubled. (Santander is characterizing it as a “technical issue.”) Those transactions included those from 2,000 businesses, as well as accidental deposits across 75,000 accounts of individuals and companies like a corporate Ebeneezer Scrooge who’d been scared into generosity.

The bank is now working to undo that generosity, Santander confirmed. Unfortunately for Santander, many of the deposits were made to accounts at other financial institutions, including HSBC, Barclays, and others. Santander will now use a process called ​​“bank error recovery” to collect the funds, though it’s unclear how many individuals have already spent the money, which could make this process a nightmare for the bank.

Incidentally, large sums of money being whoopsed into the wrong accounts is not uncommon. In April, the New York Times reported that a Louisiana woman was charged with fraud after failing to return $1.2 million mistakenly deposited into her account by Charles Schwab, which had originally intended to move just $82.56 into a Fidelity account. Kelyn Spadoni had used the funds to buy, among other things, a house and an SUV. She was subsequently fired from her job as a 911 dispatcher.

Chase Bank, meanwhile, mistakenly deposited $50 billion into a Louisiana man’s account earlier this year. In a statement to CNN in July, Chase Bank blamed the issue on a “technical glitch,” adding that the account was ultimately returned to its correct balance.

In most cases, as with the aforementioned goofs, mistakenly deposited funds should be returned. One notable exception is Citibank’s $900 million mistake. After accidentally wiring nearly a billion dollars to hedge funds, some of those hedge funds decided to hang on to the money — and a court ruled that was perfectly fine, due to pre-existing loan terms and convoluted systems Citi had in place for sending funds.

Unfortunately, “finders keepers” likely does not apply to the Santander crowd.