Bad service

the worst service ever received from National security, i called Chubb to cancel my contract with them after i sold my house, i was advised by Milaan Sango to send a written cancellation to them because we can't cancel over the phone which i did, it was in APRIL 2019. i never received any communication or acknowledgement of receipt, after 2 months realizing that they still debiting my account i then tried to make further attempts to get hold of them i eventually managed to get hold of someone who then promised that they will sort my issue out, her is Jacoline Mothiba who promised to help me sort this thing out, she even went as far as sending me a screenshot of their system showing that my account has been cancelled but to my surprise every month i'm getting threatening emails and SMS from Alliance. This morning i received an email from Alliance again stating that they handed my account over Credit Bureaus. I want to know why am i still receiving SMSes and emails from Alliance and Jacoline Mothiba stated that the error was from their side and they'll communicate with ALLIANCE to remove my name from their Data? I also want to know why is Milaan Sango so quite because she is the one who gave an instruction to send a cancellation in writing. she never responded to my emails not even once. what kind of a service is this. Can they please remove my name from Credit Bureaus because i have all the correspondence that the error was from their side. Jacoline also advice that because followed all the proper cancellation process and they further went and debit my account for 3 months i don't owe them anything. i'm surprised to received this email