Disgusting service from mtn south africa

I had my sim card on roaming with mtn number ********** 371;i used this number for banking sms and to receive calls;constant sms from the bank are received on this number;however mtn stopped the service on my number and asdigned it to someone else;the reason being it was unactive for 90 days which is a big fat lie as i constantly received sms on it meaning it was not unactive.i end up escalating the matter with no success.now i found myself strended in a foreign country being unable to access online banking as my banking was linked to that number.please do not use mtn as a network they dont have a good client service and do not listen to their customers.Disgusting service for a faithfull and long client