MTN unacceptable service.

My mother upgraded on her business contract with MTN and in the contract they said that you get 20GB data once off as a promo she upgraded to the note 20 ultra and did not receive the 20 GB data that was 3 weeks ago since then all they tell us is that they did log a query every time we call its the same thing over and over this is unacceptable service!!!!!! Plus the staff of the stores would rather tell you to shut up when you are in store this is just wrong. Can't they do something about this poor service!!!!!!