Bad service

I am with mtn for 22 years with the same number . On the 20th April a sim swap was done on my number by an unknown person. Online purchases were made using my number. I requested to get my number by doing a sim swap but the problem is, now I can only receive calls but can't make outgoing calls. I made numerous visits to the mtn store n have been calling them for over 2 weeks to sort it out. Every time I call I am given different stories. Do they not know the reason as to why I can't make calls n try to fix it. Its so easy for a *****ster to do a sim swap , but we original owners of our number can't get help from mtn. I'm disappointed after been with them for over 2 decades. Customer care staffs really has no clue as to what they are doing. They seem lost coz they have no answers. Its sad to leave mtn but they leave me with no choice. I have had enough.