MTN poor service

They stole my phone yesterday at Rosebank, since yesterday my phone is on have tried to block they are telling me many stories, I brought affidavit still no help have been a client for more than 14 years use more than r1500 airtime every month and it's on record but still I'm treated like **** I'm changing from MTN to Vodacom MTN is useless. Now ********* are moving around with my aim card