Standard bank does not want to help!

My father is the only director for the company I work for and he sold one of his houses about a year and a half ago and someone didn't do their job right at Standard bank because the house is still showing on his credit profile that he isn’t paying it, according to my knowledge this is ******* as banks are required to send updates of people to the credit bureau’s regarding changes on accounts. Now in order for us to resolve this matter ourselves we need a settlement letter from the bank stating that the the account for this house is no more. We have tried phoning standard bank on multiple occasions and the one agent send us to the next and so forth, never ending circle of agents and still no results. We have contacted the VAF department of standard bank as-well via phone and email and no response! We desperately need that letter because we need to upgrades our cellphones and that account is blocking us from doing so for the last year and a half. My father also can’t apply for any credit due to this matter being unresolved. His credit score is very good but this is the only thing standing in our way! If there is anyone who can help us with this matter please contact me.