Worst service provider don't go there

I have never experienced such bad service from a service provider. They keep on debiting my account but I requested them to cancel my data contract 4 months ago. How can they perform such kind of ***** from individuals. I honestly failing to understand how they operate. No one responds to my emails. I have canstantly been receiving the same email over and over again someone asking me to send my documents through which I did 8 times already. They also just decided to double up my debit order. This is really disappointing