DOUBLE DEBIT AND STILL ON 22 OF THE MONTH NOT RECEIVED MY REFUND?

My cell account is set to process automatically via a debit order. This month such debit was processed twice. (Duplicated) On 02 May and again on 03 May. I visited Cell C and to date 22 May STILL HAVE NOT RECEIVED A REFUND, despite at least 10 interactions with Cell C.