Capfin disgrace

Paid in an installment the day my debit order also went off. Now struggling to get a refund! Must according to them go the bank and get a stamped proof of payment!!@ payment was made from my personal account. I am currently not able to go to one of the fnb branches as I am staying very far from one. How us this possible? Payment reflects on their side and on my transaction details! Disgusted!