MTN YOU A *****!!!! AND DISGUSTING SERVICE

I have had just about enough of the bad service received from MTN. My fiance has a contract and his normal amount that gets paid monthly is R341 but on the 1st July MTN tried to deduct R1541.36. ALMOST 5 times his normal amount and nobody can give me answers. And to make matters worse, they go an suspend his line for non payment but we have an open query regarding this. SORT THIS OUT MTN. When you try and call the call centre you hang on for days. DISGUSTED