Air Asia — Price paid for name change

We had book 9 tickets from Hyd to Goa round trip. Unfortunately due to a change in last name for 4 passengers we were asked to cancel the tickets and rebook. We were told the charge for cancellation would be RS 3000 per persons and of RS 36556 we got a refund of RS 5737. We booked then tickets mean while again for the 4 passages and paid another RS 33968. We called Air Asia and they told us after the cancellation that the cancellation change was 3000 per person per way. I have paid 8534 per ticket and got a refund of AED 1434.25 per ticket. It’s a joke that took 28399 from me just for a name change. I have not even changed the dates of my travel. This is not fair