Cancelling of Vodacom insurance

I cancelled my insurance with Vodacom Insurance in the beginning of March and they told me that I will get a refund because I paid upfront. They deducted another payment on the last day of March. I called to ask why this happened, in the beginning of April,after I tried calling a couple of times on their number, I got through after 17min on hold. The lady promised that there will be a refund and she cancelled my insurance. Another payment went through yesterday. I tried to call again today and after 15min of holding...no answer. This is absolutely ridiculous. Can someone please get back to me ASAP ***