Legal action maybe perused.

All my debt has been paid and cleared 6 months ago, I've only received one paid up letter out of four and I've been placed and left on ITC. This is ridiculous irresponsible and negligent at this point I've made several attempts to call and sort the issue out but it's either I get through to the call centre and before I can get details or sort the account the call drops, while on other occasions they just drop and say they'll call me back which has never happened at this point I'm will to take this matter up with lawyers and sue on the grounds of misconduct and negligence based on not having accounts being handled correctly. And apparently, I'm not the only person that has this issue.