Service Line Warranties of Canada

On August 4, I made a payment totaling 140.99 on my credit card because the cheques I had sent for this service were not received in time. On or about August 14, they cashed the cheques but failed to refund me the monies paid by credit card. I have been in touch twice with these people trying to get a refund. My last conversation was on August 25 when I was promised a refund on my credit card within 7 business days. As of today, I haven't received a refund. I trust you can get this resolved for me.