British Airways — Partial ticket refund for flight delay more than 24 hours

I booked 2 two way tickets from Hyderabad to Montreal(Canada) via London(HEATHROW) for 4, 91, 368 rupees with booking id:NN2F1DUBN8BZ6V288313, ETICKET numbers:125-[protected] and 125-[protected], PNR number is NDNMYM through MakeMyTrip. The onward journey is on 9th July 2022, and the return journey is on 12th Jan 2023. The return journey flight is delayed by more than 24 hours we were told that we will get full refund as per the British airways policy. So we went ahead and cancelled the flight on 7th Jan 2023.The refund is processed on 18th February and the refund amount issued is ₹48554. We lost lot of money because of wrong guidance.