Payment deducted for cancelled contract

Called cell c on 03/05/2018, call reference ********** ********** 29, to cancel a data contract. spoke to a lady by the name of Princess who advised that the cancellation will be effective after 30 days notice was given, notice was thus given on 03/05/2018. All services to the line was cut on 03/06/2018 however I was still billed for the entire month of June. Today, 01/07/2028, another payment was deducted. Please contact me to arrange for a refund or reverse the debit order or I will take this matter further!