Uncancelled debit order

I ordered Samsung J7 cellphones , 2 for R220 per month . They delivered 2 smart turbo 7 Vodafone. Then I returned them the same day because it's not what I ordered . I called to cancel the debit order. Then on the 15th of September they deducted the amount of R207 . I went to my bank to reverse it but then they deducted another amount of money again on the 16th of September the amount of R 100. I called a consultant named Mary Mashego and said she cancelled the debit order. I've even decided to change banks because FnB bank won't help. The contract is under Vodacom and I already have existing contract under Vodacom for 2 cellphones. The company never contacted me to say they have received the phones I returned. I called again and they said the debit order is not cancelled as promised. They said they recorded the calls .