CELL C BAD SERVICE AGAIN!!!!!!!!!

At the beginning of June Cell C did not debit my account even though there was more than enough funds in my account. I called and they told me THEY were having issues with debit orders and would re submit. One week later I called and asked why they had STILL not debited my account, again they apologised and said they would re submit. 5 days later I called AGAIN, and they requested I rather do an ETF which I did and emailed proof of payment. On the 1st July they double debited my account, when I called they said I was in arrears!!!!! I was furious, I called and re send my proof of payment to 3 different email addresses. I also posted it on Hello Peter, the response was we will contact you. They have since acknowledged THEIR mistake and said they would refund me with in 7 -14 days. ITS NOW BEEN 22 DAYS and they have still not refunded me and i fear they will still debit my account again at the end of the month. I have called twice and No one is able to tell me when i will receive the money they stole from me??????