GoAir — Go Air Domestic Booking

I had done a booking for 2 tickets in Jan for travel to and back Mumbai - Cochin in May which was cancelled due to Covid. I was asked to change the dates at an additiional fees of Rs 2000+ which I did for Nov 12 to 16. I get a msg that the said flight is cancelled and can change booking for the next 1 year. When I go for a change booking for 1st Nov21 and return on 4th Nov, I am asked to pay Rs.11660. This is utter nonsense victmising the existing ticket holder who has already paid money and has not enjoyed any service . I want the monies paid to be returned.
The PNRs are DYZ9ND and WC6L7N.

SANTOSH MENON
[protected]@gmail.com