Refund takes forever

I made a flight ticket purchase which was then canceled because of availability, or so they said on their side. A refund process was initiated, which was supposed to reflect in 5-10 business days. After a month I still hadn't received anything. They kept saying the delay was with my bank and that they had already processed it. My bank told me that the payment was on hold on the company's side. I had to send emails after emails to them and skycanner. I even reached out via Twitter. I only got back my refund after sending plenty of emails.