Still waiting for a paid up letter

Phoned the above mentioned companies call centre on the 02 March 2015 to inquire about receiving a paid up letter on a account that was outstanding. Was told that the person that checks to see if the payments where made into their bank account was not at work but the following day I would receive a call to verify that the money reflected in their account. Up to today I have not received any feedback and when you call the call centre they keep you holding on for long periods. The last time was over 20 minutes !<br> Please can you send me the paid up letter.