Disgusted by Lakeside Mall branch staff

What a terrible service I recieved at Lakeside Mall branch. The consultants are rude and not helpful at all . I went there to do a sim swap since I was overseas for months and when I got back I found out that my sim is missing. Unfortunately I didn't get their names but it was an old lady and a guy with dreadlocks. I'm very disgusted as I've been a loyal mtn user for years. They are say that the number is inactive but it hasn’t been give to anyone. Now why can't I get my number back? It's shameful how mtn as big as it is has been reduced to a terrible service provider. My number is ***