Endless account issue

I am having an endless problem with my account. I usually pay my account in cash at Shoprite. I made a payment of R725 at shoprite on 2 August 2018. Until now this payment is not reflecting on my account. I have send countless proof of payments through to ********** Contacted the social media team who have tried to assist me but 3 months later I still find my self having to call in to get this issue resolved. Today my outgoing calls have been suspended due to the "arrears" balance. I have called the collections department for the last 3 months. Most of the agents appear arrogant and rather say don't pay at shoprite than try to assist in resolving the issue. I have spoken to 2 supervisors who have promised to escalate the issue however until now nothing has been done. Oddly enough most of the agents I speak to say that they can see the payment notification on the system. So why is this not being allocated to my account??? More frustrating is the fact that any one that I speak to can only "escalate" the issue to the finance department.