Contract signed under mis-information / No contract cancellation & refund

I signed a contract for FIT24GYMs new Athlone Gym on 29 June, but then realised I signed under incorrect / mis-information from their sales team (interest charged on my credit card despite confirming verbally that there would be no interest, conditions of cancellation not communicated despite twice verbally confirming that there were no penalties for cancellation). I then tried to follow up with Sarisha (Admin) & Etienne (Sales Manager) on contract cancellation. After numerous attempts (multiple emails and phone messages over a week), Sarisha eventually emailed me to confirm receipt of my contract cancellation instruction (sent within 5 working days of contract signing). I was promised a full refund by 25 July.

But 25 July came and went, and there has been no reversal of the budget transaction, and no refund of the two budget payments from my account).

Again, I have emailed and left phone messages for Sarisha (at least 3 attempts per communication mechanism over 7-10 days), and she has yet to acknowledge my emails / messages or respond.

This now needs to be escalated to Executive Management, so that FIT24GYMs does me the basic courtesy of responding to my multiple communications attempts, and refunds me the full amount plus interest and other charges related to this matter.