Payment allocation

I’m really frustrated with Payflex, there was a refund because I had returned the items back to Superbalist. The problem is that the refund got allocated to June instead of being allocated to May, now it shows that I am owing but I am not, there is stop order for the 15th .I sent emails but no feedback. Called the call centre but it’s automated and it states they cant take my call, I must login online. Watsapp can’t assist.