ADT after sales

I missed to payments last year and it was brought to my attention when I did a credit application. No way was I informed by ADT that I was on arrears. It is a bussiness account and account is not handled by myself. In end July in settled this arrears and requested a paid up letter from ADT to rectify my credit profile . I contacted ADT several times , spoke to several consultants in Cape Town and nothing , absolutely nothing as been done . I so fed up because my credit profile is now adverse until I receive this letter . I can't wait for my contract to end Dec (2025 ) never to renew . ADT is just bad news with after sales. Requested new boards to no avail . Cannot believe a huge company just neglect you once you sign up . No problems with armed response . Just after sale enquiries is pathetic .