Pathetic service from Telkom!!!!!!

I am struggling to cancel a contract at Telkom for some time now. The modem doesn't work in the area where I live. So I am paying for a contract that I don't use. I went to the Telkom Branch 183 Nelson Mandela Dr, Shop 8, College Square Center, Bloemfontein, 9301 a few times to cancel the contract but the contract is still not cancelled. I talked to the call center as well and they gave me an email address ********** where I had to sent the proof op deductions from my account, so I did sent a email with the proof of deductions from my account on the 11 of July 2018. They called me yesterday and told me that I owe them a lot of money and that after I went to the Telkom branch and sent an email as they requested. Now they want me to register on the Telkom website to cancel the contract, but I am struggling to register because it says: "Oops something went wrong, please try again later" I already tried about 10 times again and nothing change.