MTN - 6 Months my number does not exist

In November 2023 I ported to MTN, ever since then I stopped receiving calls from other networks - it states that my number doesn’t exist. I can only recieve calls and messages from MTN only.

I have been going to their branches, calling their help service line and got a reference number: SCM/*** in which they said it will be rectified within 24hrs. I have been waiting since. This is disappointing for such reputable company.