Make My Trip - Visa cost Refund delay and not fully Refund.

I had booked land only deal to thailand. as per that the visa is included in their scope. However ** days before travel, i had received mail that visa may not be able to process due to continuous holiday and makemy trip asked me to take on arrival visa on my own and they would refund the same. I had even written mail on this.
I did as per that. but after my return when i claimed the visa amount, they started giving excused and refunded only around *K against approx **K i spent.
They are not responding or ready to refund the actuals i spent even though i sent them the visa receipt.

Its took around * months for them to settle even ****. They in between reject claim too.