Allied Irish Bank (AIB) has apologised after some customers who are unable to withdraw money from ATMs.
They had problems at the bank's cash machines because they were mistakenly registered as being over their daily limit.
A statement from the bank said: "We are investigating this issue and are taking all necessary steps to resolve it as quickly as possible.
"AIB apologises to all customers for any inconvenience caused by this issue."
The bank's customers using AIB ATMs could be affected if they have previously attempted to withdraw funds at a non-AIB ATM earlier in the day, where the total value of their attempts was greater than the daily €600 limit.
An AIB spokeswoman said: "The issue still remains with non-AIB ATMs. People are only affected at AIB ATMs if they had previously tried to withdraw cash."
She added: "Customers are able to use their AIB debit cards to withdraw cash at AIB ATMs, point of sale terminals and online shopping channels."
AIB customers using AIB ATMs might also have had problems if they had previously attempted to withdraw funds at a non-AIB ATM earlier yesterday where the total value of their attempts was greater than the daily €600 withdrawal limit.
AIB credit cards are working as normal.
Furious customers took to social media yesterday to voice their frustration at the glitch which struck just days before Christmas.
Bank of Ireland customers also had problems on Friday.
The bank confirmed that an incoming payment file was delayed overnight but said yesterday morning that the issue had been resolved.
It is not known how many customers were affected by the delay to the payment file.