BAD customer care

hi my name is alisha  I live in ohio we have been with t mobile  for 16 years  my daughter  got a new phone and it was sopost  to be a promotion  they are now saying it wasn't  and making us pay over 700dollers for the phone they lady  on the phone was a manager  she wouldn't  give us her ID number  or her last name as a customer  for over 16 years  you would  think they take better  care  of u then this on top of it all she had noutheing  but problems  with the phone  they did something  and it caused  her to have to change her number  that she had for 16 years  as of Monday I am changing  phone  company's  if I was you  I would not have t mobile  for a company  cause with in the last year  they have went to hell and don't care know more  about there.custerms thank you alisha