Horrible experience with Kenya Airway Customer service poor service failing to refund

I'm writing to express my extreme disappointment with my recent experience. i bought 4 tickets from South Africa to Canada for 4 children R54 000 . upon following up on what will be needed for the children to board the plane they said no we cant carry all 4 kids, request for a refund i requested a refund only 2 tickets were paid with a charge of 5000 rand on each ticket. now we are battling to get the refund for the other ticket, their customer service is advising that payments were finalized speak to your bank, on all ticket the charge 940 USD i received R20 000 back, how on earth is the refund completed is 34 000 rand equivalent to 940USD?