Poor service

I have previously ordered many times on the Mac website. However in November last year they canceled 1 of my orders in error and promised me a refund. After numerous calls, emails and whatsapp messages, I have not received my refund till date. The call centre is situated overseas, they can't help me, they can't escalate, all they can do is say sorry! On email I was told 3 to 5 days, on whatsapp I was told the refund takes 30 days. Nothing yet!