Roaming not requested

I received an sms from mtn saying the roaming service has been added as requested. I did not request roaming service so I have to assume there is ***** taking place on my number. I tried calling the call center but after numerous dropped calls and been kept on hold I've given up. Ease tell me there isn't anything untoward taking place on my number as the sms suggests!!! I am worried and have already wasted nearly an hour of my life and this matter and gotten nowhere