Unable to confirm details unless I am on a banking app or on cell phone

Unable to confirm details unless I am on a banking app or on cell phone-Contacted *** I have been under debt review for the past 5 years and have basically closed the FNB checking account as I have been paying it off for the last 5 years. Now that I am close to having paid it, FNB puts a debit on 27.05.2022 of 8344.66 (which was way more than what I started with) and I cannot even get to know why because I cant be verified-UNLESS I go to the branch and get identified. I still have access to my Online account but that will not help neither. I do understand that security is very important, but surely this level of inflexibility is not acceptable. I am unable to go to my branch until Saturday (4 days from now) as I cannot take time from work as there is no one to relieve me. My cellphone number is still the same as FNB has on record and that will also not help. I am really not happy with this service. It seems that its OK to charge a client with some IMAGINARY amount and not inform the client of this-that is acceptable...where is MY security?