Worst customer service

I regret the day I ever did business with cell c, its been more than 2months that I paid up a contract that I had with them and daily its a struggle to get them to give me a paid up letter, I have reached out to their Facebook and Instagram pages without success and each time they respond its either they ask me to forward things that I forwarded more than 10 times already or they promise me that someone will get back to me which it never happens, all they ever tell me is that their legal department is busy with my query. My question is that does it take their legal department months to draught a paid up letter as I sent them proof of payment last year October? I would not recommend this service provider to anyone.