Frustrated

I have an African Bank account that you can get rewards with. Except I can't get my rewards and no-one at the bank is able to help me and I can't get on either the app or on internet banking as it won't allow me on. I have done everything they told me to do, including re-registering, but to no avail. To try and phone the help centre takes forever as they take forever to answer their phones. Please can someone assist me so I can get my money from the rewards