Terrible Customer Service

Terrible Customer Service. They don't even deserve 1 Star. I have cancelled my contract in Feb, paid the amount outstanding in March and it is the 17 Nov 2021 and they have handed me over not allocated the payment. I have phoned once a week since then and still nothing, emailed the proof to ***; ***; ***; ***; ***; *** I have so many escalations numbers and ref numbers it will blow your mind. How hard can it be to just do a simple thing, really this is ridiculous and so frustrating how they treat their customers. I am going to have bad debt, a bad name all because they cannot allocate a payment and give me a paid up letter, I have to phone every week since March 2021 to follow up and every time they transfer me of give me a new email and ref number with false apologies. I ask them every time please update my cell phone number and phone me back, they never do. I have followed all the steps, done everything they asked me to and this is how they treat their clients.