You messed up my life

I am sitting in a situation where you made an error by debiting the incorrect amount from my account for more then a year. And this has messed up my credit record so badly that I cannot finance anything at all because of your mistake. You phoned me and appologised for the error and reversed R5000 worth of interest. But this does not fix the fact that because of your account i cannot finance a house. I am sitting in this situation cause you are reporting that i am in arrears for about 18000 how long will this take me to pay off so I will not be able to do anything because of your mistake.