Bill constantly wrong

Does anyone else have a problem with their bill constantly wrong? 
My bill has been higher since I switched and it keeps going up with no explanation.. 
I called in and had the upper mangers say that they would correct the issue and still nothing. They even have it in their computers what it is suppose to be and it always too much..  
Is this a common bait and switch with T mobile where they hope you get tired of calling in to deal with incorrect billing tactics? Any help is appreciated.