Non-existent customer service

I called in to the customer service department to ask for assistance to submit a return on 23 July - I was unable to select a refund on my side for some unknown reason and the agent submitted the refund on her side and took down my bank details to process the refund accordingly. Then, to my surprise, I received an email on 31 July to say that my store credit had been refunded! I immediately emailed back to say that I did not want store credit and that I was supposed to receive a refund. (I still have not received a reply to this email.) I called again on 6 August and spoke to an agent by the name of Natasha who then asked me for my bank details again and assured my it would be sorted out immediately and that she would send me an email to confirm our conversation - needless to say I have still not received my refund or an email from Natasha. I can't get through on the contact number anymore, emails are being ignored, social media seems to be a waste of time too. All I want is my money to be refunded for the goods I no longer have in my possession. Why would I want store credit if the service is this bad??!