Credit Status not up to date with ITC

I am disappointed at ABSA, i have been paying for my vehicle and i have not missed one installment with them but to my surprise i went to apply for a contract phone and it was declined, i was told i have not been paying one of my accounts. When i check with Trans union it showed that i am in Arrears of 150+days with Absa Vehicle Finance yet my account with them is up to date. When i call ABSA no one is willing to assist me they have transferred me from one section to another with no solution yet they are telling me that the account is fine with the, it is up to date but with trans union it is not it was last updated i February 2015. This has affected my credit record, status and scoring. No one at Absa wants to take responsibility and honor for the mistake they are blaming their credit bureau section which i can't even get through to them, the number that the consultant gave me is not working. I am so upset because this has affected me just because ABSA did not their job correctly since i have not missed any payments with them and they also agree that the account is up to date but it's not updated with Trans union and now it leaves me a bad name and bad record/.