A charity lost more than £30,000 when shop staff mistakenly refunded a customer £90,000 when she returned an item worth £9, a court heard.
Comfort Konadu, 52, received the unexpected windfall after she visited a Royal Mencap Society branch in Openshaw, Greater Manchester, in October last year.
Shop staff unintentionally added two noughts and four other figures whilst entering the electronic credit note into the till for a refund for the grandmother, who was returning a bric-a-brac object.
Konadu then transferred £57,000 into other accounts including her family members in Ghana, Manchester Crown Court heard. The 52-year-old cleaner admitted theft and was sentenced to 15 months in prison, suspended for two years.
The charity managed to retrieve two thirds of the missing money but £31,000 remains outstanding, which represents 18 months worth of profits for the charity shop. Konadu is now expected to face a proceeds of crime hearing to return the sum.
Sentencing Judge Nicholas Dean QC said: "This was an unexpected windfall that the defendant took advantage of. She must have realised this was an error. It would be very different if she had somehow contrived to obtain credit in the first place. That's not the case and she fell prey to the temptation to use the money she knew perfectly well wasn't hers."
Two workers at the charity were suspended and subsequently dismissed over the mistake.
Konadu, of Openshaw, initially claimed she had been expecting £12,000 into her account from another source and said at first she assumed she had legitimately received the money.
She said when she was realised it was higher than expected she had tried to raise the issue with her bank.
But inquiries revealed she didn't inform the bank or the charity about the botched transaction.
Max Saffman, defending Konadu, said his client has been in Britain for 15 years and worked as a cleaner since she arrived in the country.
He said: "Until his windfall she was leading a very very modest lifestyle and she is a hardworking lady the vast majority of the time. The money was more than she could ever have dreamt of and temptation got the better of her."
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