Updating Information on ITC

FNB has the worst collections department i have ever had to deal with in my life. i paid of my Credit card in Full and received my paid up letter over 2 months ago but im stil listed on ITC as owing going into the 3rd month To date iv sent countless emails, went to countless branches called every number listed on their websites but stil nothing is moving. Please advice me on what to do becouse i need my information updated