Sales Rep said we can change account holder later

My bf and I signed up for a black tag in October last year. But because I didn't have my ID or any identification on me the contract is in his name. The sales rep said we must come in the next day with my ID so we can change it over to my name. When we went back the next day they said they can't do it in store. They are using my address and my banking details. Yet they want to charge nearly R900 just to change the contract to my name?<br> <br> This is such a disgrace