Cancelled contract

We take out contract with cell c in February 2019. WE RECEIVED THE PHONE AND WAS THE WRONG SAMSUNG . WE CONTACT CELL C AND THEY ARRANGED FOR RAM TO COLLECT . WE ALSO CANCELLED TEHE CONTRACT. BUT NOW CELL C IS STILL DEBITED OUR BANK ACCount. We phone the 084 143 option 2 number numerous time they keep on putting us thru to the follow up department. Who never answer phone just music playing . When will you refund my money you deducted from my bank account. I will go to credit ombudsman if this is not resolved.