FNB - incorrect charges !

Hi - Almost every month I get charged unpaid mag tap fee of R115 - When I call or using the service suite FNB Views my previous profile and find out that the faults on their side. They will we refund me. But the it takes 5 business days. - Yes! I know you guys are giving my money back but This can’t be happening every month!!! When they are funds in my account- Please look into this matter further