Bad customer service.

I recently got consolidation loan from FNB and they paid your account on the 13 April 2018 via EFT. I have tried calling your call centre countless times and no one is picking up my calls. I have emailed customer support and they told me I should provide proof of payment which I did. They came back requesting detailed proof of payment and I provided that again.Ever since I haven't receiced even a single call or email to inform if they are looking at my issue.