No paid up letter

My exact account was handed over to the above mentioned supplier last year. They contacted me and we made arrangements for payment. The debit orders went through my wife's bank account and the final payment was in November 2014. <br> <br> My wife and I have been calling to obtain the paid up letter however even now we haven't received one. My wife called this morning and they said they will call her back. I have complained earlier this week that I have been getting messages that I need to settle my account while it is paid up and I was told that they have a technical problem on their side.<br> <br> When we made an arrangement a promise was made that after payment I will obtain my paid up letter. Please help as now I feel like these people are ******.