Indigo Air lines - Not allowed to board the flight

I am writing to express my deep disappointment with my recent experience on flight *E *** (PNR: F**MKQ) from CCU to BLR on October **nd. Despite completing web check-in to streamline my journey, I encountered a series of issues. I arrived at the check-in counter at *:**, only to be informed that I would need to carry my check-in luggage onboard as the cargo had already closed. During security, I complied with regulations and disposed of restricted items. Arriving at the gate at *:**, I was denied boarding, even though ** minutes remained before departure. I requested assistance, yet the gate staff refused. Ultimately, I had to purchase a ticket for the next flight, only to witness passengers being boarded past the *:** departure time. This inconsistency and lack of assistance were frustrating and unprofessional.