Waiting for my refund

Money has been deducted off my account, from an old account which I was using when I was a Cell C customer +- 10 or more years ago. I recently decided to port to Cell C again, gave new banking details but then sent the phone back due to it not being user friendly. During the time that the phone was being assessed, Cell C accounts decided to debit my old account twice, the 1st time there was no funds in that account and the bank charged me R150 in fees. I need my money back that was taken from my account on 31/8/17, an amount of R402. 31. Please can I be contacted so that this money can be refunded into the right bank account asap as my calls and messages have gone unanswered. Because of this oversight from Cell C, I have had to pay R150 to the bank. This is a lot of money which I feel Cell C should take the responsibility to pay back as well.