Unable to get paid-up letter for the account i paid

I had a credit card account which was handed over and I paid all the money that i was owing, the problem now I can not get the correct department which will give me a paid-up letter, when i call they transfere me from department to department, I am now tired of this, it is time and money wasting, credit card account number is: ***. I need that paid-up letter to clear my name