15 days and still no refund

I have been waiting 15 days for my refund. Their driver cancelled my order and I had to go hungry, because I had already paid via card on the app, they said it would take 2-5 working days. Hardly any contact with me. I keep phoning and when they do answer it's always a different person and noone can tell me when I will receive my money back. *************. Unreliable.