Some Bank of Ireland customers have had their debit or credit card restricted.
It's after concerns the cards might have been compromised.
Those affected have been notified by the bank, and will receive a new card.
The bank says: "When we suspect that a debit or credit card may have been put at risk of fraud we take precautionary measures and issue customers with a new card.
"A risk of fraud can arise, for example, if an ATM is tampered with or through a third party data breach.
"Receiving one of these precautionary messages does not mean that your card has been used fraudulently."
It says some new cards have been issued as a precaution.
Impacted customers can still use their existing card for chip and pin transactions in ATMs or in shops using their four-digit pin.
But online and contactless functionality has been removed.