A technical problem at Bank of Scotland has led to some customers being charged twice for in-store purchases made with chip and PIN cards.
The bank says it made an "error" in processing debit and Visa card transactions which has affected "a small number of people" using chip and PIN payment terminals across the UK.
The problem has been fixed and the bank is "working to make sure affected accounts are automatically recredited as quickly as possible".
Earlier this year a glitch at Allied Irish Bank led to some accounts being debited twice for cash machine withdrawals.