Cell C: Incorrect active debits

My wifi contract with Cell C came to an end in May and i gave them a call sometime in June indicating that i will no longer liker to continue with their services. They confirmed that my last debit order will be on the end of June and my current services at the time would expire on the 12th of July. The services did expire from July but they're still debiting my account. I cannot get in contact with them as my number has expired/inactive. Please may i have some assistance.