Trip.com Failed to Transfer Extra Baggage to Rescheduled Ticket

I purchased a ticket through the Trip.com app and later changed the date of my flight. During the final step of the process, the system canceled the original ticket while charging me, yet the 10 kg extra baggage I had paid for was not carried over to my rescheduled ticket. This has caused significant inconvenience.

Despite multiple complaints, Trip.com has shown no willingness to resolve the issue. Their lack of customer support and problem-solving is extremely frustrating. I will never book a ticket through this app again. I expect Trip.com to address this matter promptly and compensate me for the extra baggage I purchased but could not use.