Poor service by mtn

On 15 September i was debited for 3 months in one month after having paid Prorata and 1st installment i have tried to get help with the refund you talk a different person everything i call no one can help me the REQ are closed without being resolved. They have the nerve to tell me they can't see the money we pay upfront so it's our duty to call and have them allocate it to my account yet I sent the proof of payment before they could deliver the router and sim. I have been calling since the 17th of September till now. No one is willing to assist when I ask to speak to a manager I'm given the run around till the call cuts and no one gets back to me till I call again it's been the worst experience 💔