Transunion not helpful

I have an account that is showing as a default on my credit report. The financial institution that provided me with the loan gave me paid up letters and they say they have sent everything to transunion however this has not been updated. I have been fighting this for over a year now, the last time I called transunion they told me to send an email and my quiry would be resolved within 40 days. Its been over 60 days and no one from Transunion has bothered. In the meantime I cannot apply for credit. Would really like some answers because this is now beyond ridiculous.