Pathetic Service

I have recently settled my account and all I'm asking for is my paid-up letter. I was told the payment will be allocated to my account and then it will be closed, which will generate a paid-up letter. I have spoken to so many agents and they just say "it will be escalated". I wouldn't be calling for this letter if it wasn't important. I'm busy with a housing application and this is delaying the whole process. I'm shocked at this bad service for something that is so simple. My instalments were paid on time, there was never an issue - just provide me with a freaking paid up letter!!!!