Failure to assist with sim swap

I am so disappointed that after more than 15 years using MTN as my subscriber using only contact number, MTN is unable to help me with a sim swap. Now I cannot be able to receive important, access my e-mail and everything that I registered online because I cannot be able to receive OTP's. I once heard that MTN does no longer want to do sim swaps for customers the belittle or take for grated. I am very disappointed after using MTN for such a long time. What a poor service I had???!!!!