Customer service won't assist with debit order reversal

Good day customer service, Today I tried to reverse a debit order which I instructed the other party to move it to the last day of the month. As usual I completed the relevant bidvest bank docs and emailed to customer services. A few minutes later I received an email from bidvest bank telling me to take this matter up with the merchant. Tried to contact the merchant but no one could assist me. My question is why have this service for reversal if you cant assist me? Can somebody email me and give me a proper reason why you cant assist me?