Cleartrip — cancelled trip because of the impossibility to update passenger information

I've booked a trop from new delhi to kathmandu using the cleartrip website in may of this year (Trip id : [protected]). I had to ask a new passport because the validity of the one i had wasn't long enough. Yesterday, i asked cleartrip to update the information and they noticed that the information on my passport wasn't exactly the same as in my reservation (My second given name was missing). I was very surprised to hear that it was impossible to update my information and that i had to cancel my fligth and book another one (My flight leaves on saturday 27th of october).

Here's the e-mail i got :

"dear annick,

??? As per our telecom, while updating the passport details it has been observed that your few given names is missing from the booking and for that matter we checked with the airline and both the airline denied on changing the name and recommended to cancel the booking and rebook with the correct name as per passport.

Further, if you are able book with us then we can waive off the convenience fee of rs. 599.00/- only airline cancellation penalty of rs. 2000/- and insurance amount of rs. Rs. 1, 662/- will be deducted and rest of the amount of rs. 13, 858/- you will receive.

You can reach out to us on chat in case you do have any other questions.

Thank you for choosing cleartrip for your travel needs.

Regards,"

So i cancelled my flight and booked another one, and today i got this e-mail :
Hi annick,

We have processed a refund of rs. 8, 956 for your new delhi - kathmandu return booking (Trip id [protected]). The refund should appear in your account in 5 to 7 working days depending upon your bank.

Computed refund details
Description amount
Gross amount (+) rs. 16, 608.00
Cashback (–) rs. 750.00
Discount (–) rs. 0.00
Net amount rs. 15, 858.00
Airline charges (–) rs. 5, 005.00
Cleartrip charges (–) rs. 1, 298.00
Service tax (–) rs. 0.00
Cleartrip service tax (–) rs. 0.00
Convenience fee (–) rs. 599.00
Total refund amount rs. 8, 956

So i'm really not satisfied, because the fligth cost me total rs. 17, 520 and i got only half back, and not the same amount as they anounced.

I'm asking for a better refund.