Indigo Airlines — Indigo Airlines- Not allowed to board flight

I booked my flight from Indore to Nagpur on 18th December 2023. The PNR was GZBGVQ. I checked into the airport well before an hour. My bag was 14 kg and despite my ticket mentioning 15 kg allowed in check in bag, I was refused check in as the Indigo staff mentioned that ATR aircraft only allowed smaller bags with lower weight limits. Despite multiple requests, I was not offered any assistance from the staff and was not allowed to board the flight. I would request a full refund and severe penalty due to gross negligence and unprofessional behaviour from the staff.