They won't cancel my subscription and they network is terrible!

I've had a terrible experience with Telkom. I have been trying to cancel my month to month contract. I have submitted on my telkom app with all the required documents. When I try call the call center the number is always unavailable or no one answers. I've had a call from a sales agent and he confirmed that he could see that I submitted my cancelation ages ago but you guys still want to debit from my account. PLEASE CANCEL MY SUBSCRIPTION. Your data depletes quickly and the network is shocking!