Absolutely terrible service

Payjustnow has absolutely terrible service. First I buy something at crocs, and instead of deducting the installment amount from my account, they deduct the full amount. So I returned my item and requested for a full refund. 2 days later I receive the refund back to my wallet, and I request for it to be refunded back to my bank account. They said it will take 3 business days to reflect in my account, it's been 5 business days and I haven't received anything yet. I have tried phoning them, WhatsApping them, emailing them, chatting to them, sent them a message on Facebook, I get no response from neither of these platforms. When will I get my refund and how can I get hold of this company????