MTN Port number issue

I ported my number from cell C to MTN dated 2021/02/18 - today my number is not working - I dialed 135 from the new Sim card I ported my number to 01st call 18:20 the lady told me to dial *135# opt 2 as the port was successful. I dialed my number again some guy answered.

2nd call - 18:39 a guy assist he told me to call the port department he will SMS the details to the Sim card I am using - no SMS received.

3rd Call 19:07 spoke to a Sibongile the lady provided me with the *** port department advising the department already closed.

How can we trust the service provider MTN when the consultants cannot assist? I explained my story I purchased a MTN Sim card to port from Cell C to MTN. When I phone the number someone else is answering. All I wanted was for the number to be blocked as it maybe ********** using my number and how is this possible.

The funny part is I can call out and the number shows from the old Sim card but I cannot or have not receive calls or any SMS? Is MTN working with **********?

I need this rectified ASAP - some stranger is using my number and I have used the number for over 10 years.

If ***** is committed on my personal account you MTN will be held liable as I have attempted to report the matter your consultants is useless.