How do I change my address at MTN?

I am trying to change my address on my MTN Monthly invoice/statement since May 2024 but no luck. Their famous words are "We apologize for the break down in service and for any inconvenience we might have caused you. We would like to resolve the problem and provide better service going forward." It seems to me that there is nobody left at MTN what is committed (competent) to solve this basic administration task? The MTN service shops can't help me because their scanners do not read my fingerprint?