MTN can't deliver on simple requests!

Over two weeks ago I requested a copy of my August Invoice from MTN. I get passed from agent to agent and numerous sms' telling my query was resolved. No it wasn't. Eventually I get sent the July Invoice, so I tell them no I asked for August, so then they send me the September invoice. To date there is no August Invoice. I check online to download it myself and its not there, yet they debited my account. I explained over and over again that I had until 28 September to claim the amount from work. Nothing. I lose R1000 because they cant give me an invoice. Previously invoices were emailed, then they claim to have gone through system changes and they don't bother sending invoices. I begged and pleaded and nothing. Its difficult financially because of COVID, I am using my cellphone as a work phone because I have to work from home and now I am personally inconvenienced because of incompetency at MTN. I cant even walk away, because I am tied into a contract. When the contract is over, never again will I continue with MTN. Sadly I have been loyal since the 90's and this is what I get for loyalty.