Very disappointed!

I had account with vodacom that should have ended 4/5 months ago but they are still deducting money from my account. I’m not in SA, I can’t make calls. I’ve e-mailed their costumer helpline but I never received a response. How do I get in contact with them to stop deducting money from my account and refund me my money that they’ve already deducted? This is extremely upsetting and disappointing! It’s *****!