Awful customer service

I've recently moved abroad while still having 2 data contracts that my mum and father in law are using as I am still paying for it. I had an issue with a single payment and Telkom blocked both Sim cards. After double debiting the account they kept the Sims blocked. When attempting to contact them to find out why it's still blocked, the people I managed to contact gave me invalid email addresses. After explaining my situation, they just said that I should call them and stopped replying to me. After years of giving Telkom business, I am receiving pathetic customer service. There are no email addresses or point of contact to cancel these contracts. One of which they have been charging me for, even though the contract has expired. This service is absolutely pathetic!!!