Unacceptable service re: Boxoffice

Called in December 2014 to get bank details for Boxoffice payment, once made they advised incorrect bank details used which they had given. Since then we are still having problems with Boxoffice error sms messages, we cannot rent movies en now suddenly we keep owing money due to the fact that for some reason they do not debit the Boxoffice monthly balance as it was always done. We are absolutely fed up with this, we gave to keep phoning them to rent movies, they advise that it has been resolved and with the next movie we want to rent we get the same error message and the same issue. It has been going on for 9 months now and they have never tried to resolve this. We want this sorted asap!