Trip.com Refuses to Cancel My Return Flight After an Airline Schedule Change

I purchased a round-trip ticket through Trip.com for travel with IndiGo Airlines, with departure scheduled for June 18, 2026, and return scheduled for June 27, 2026.
After my booking was confirmed, the airline made a significant change to my outbound flight itinerary. Despite this airline-initiated schedule change, I have not been allowed to cancel my return ticket, which has left me in an unfair and frustrating situation. Because the original itinerary I purchased was altered by the airline, I believe I should have the right to cancel the entire reservation and receive a full refund.
During this process, I contacted Trip.com customer service on two separate occasions. In both conversations, I was assured that I would receive an email response within one hour. However, no email was ever sent, and none of the promised follow-up communication took place. The failure to honor these commitments, combined with the ongoing ticket issue, has seriously damaged my confidence in Trip.com's customer service and support process.
I purchased this trip as a complete round-trip itinerary, and the airline's change to the outbound flight has directly affected the value and usability of the entire reservation. I should not be forced to keep part of a booking that no longer meets the travel plans I originally paid for.
To resolve this issue, I am requesting a full, unconditional refund of the total amount paid for my round-trip ticket. I also request a clear written explanation regarding why the return ticket cannot be canceled despite the airline's change to the outbound flight and why the promised customer service follow-up emails were never sent.
I expect Trip.com to review my case fairly and provide a prompt resolution to the inconvenience and financial hardship caused by this situation.