Large company has done wrong for more money "I can give more detail's"

At & t has been illegally adding money to our phone bill that we have not owed, really! up to $20.00 extra,This has been going on for a good while and i have not confronted them about our bill,

till this month .They tried to say our bill was $85.00 because changes were made to our service.This is a lie! there were no changes made to our service at all!

then they tried to say i must of clicked on a ad of their's for a discount? wrong again,i never have! they have lied on top of lied! to try to weasle out of this.Even told me they would bring my bill back down .But this does not make it right what they have done and what they have been doing to us,and what they more than likely are doing to many other people.

people everywhere are having a hard enough time without this!