My Autopage contract is not what i wanted

When I sighed for a contact with Altech Autopage Centurion branch my payment was meant to be R279pm for a closed top up contact for a new tablet for my son, they never informed me it was an open line and I have had monthly bills exceeding R 3000pm and R2400pm they did not make me aware and it was not explained that it was an open line and refuse to assist with a refund. The service I have experienced has been non existant and no body is prepared to assist and treat you like a client. I have been with them since 1993 and would not recommend them as a cellular provider as I always have issues and find the service very poor.