Online banking limited functionality

I keep on getting the following error when trying to do payments or add a beneficiary on online banking:

"Your request couldn't be processed. This could be due to a suspicious attempt to approve a transaction. To resolve this, call us immediately on ***or +***0 (international)."

I have called the number but was basically brushed off.

This happen even though I am still using the same ISP and same devices. Strangely enough, my mobile banking app works using the exact same internet connection.

This is very frustrating as I can only use mobile banking, which is not convenient when having to download payment confirmations.

Please assist.