Commonwealth Bank customers are growing frustrated with the banking giant, after another outage.

Customers were unable to access the app and online banking services for a large period yesterday.

The bank apologised to customers after the outage, but hasn’t said what caused it.

Technology expert Trevor Long said it’s not good enough.

“I think it’s a fundamental problem with the system and I think the Commonwealth Bank should be required, forced, to tell us why,” he told Oliver Peterson, filling in for Gareth Parker.

“They don’t want to admit they have problems and system failures … just tell us what happened.”

It’s the third outage in the last four weeks and Long said it could drive small business customers away.

“I just don’t think customers and businesses, who are losing money hand over foot, when they are out, should accept no communication from the bank.”

Press PLAY to hear why Trevor Long believes customers deserve answers to the outages