Refund for ammount deducted for paid up loan - Iemas

I had a Pesonal Loan with Iemas which i finished paying at the end of Novrmber but wad overcharged the ammount debited wad more than what my balance due I've send an email informing them of that and i was told that i will receive a refund which i never received again at the end of December another ammount was deducted for the paid up loan i informed them once again regarding that anf they send me refund documentation that i needed to complete and send back to them which i did i still have not received my refund i keep sending them emails requesting feedback with regards to my refund I've put a read receipt on all my email and everytime receive read receipts but i do not get a response from them. I want my refund Iemas