MTN ****med me and now billing me for their mistakes

Sad we can not give -10000 stars they ****med me and now billing me for a ****. I have spent so much money on calls and watsed so much time they ****med me and now charging me for their mistake my bill has blown up with 8k. every time I speak to someone they clearly do not understand what they are doing. they are useless not even their fruad department is functional I have sent 88 emails in the last 5 months not a single response spoken to HO no response called every single line they have suggested no assistance now I look bad and have a bill so high for a small mistake they have made and now a huge issue I can not get a car nothing because of them.