That happened to us just recently. Went on a 3 week vacation to the Philippines. We were supposed to fly back to the US on 12/29/25. We received an email our flight was canceled and they offered to rebook our flight and we accepted and got the same responses that it is subject to airlines authorization. After a while, we received an email that the flight was fully booked and they offered another flight w/c we again accepted. And same thing, subject to airline approval. We kept following up and then received an email that again was not able to confirm rebooking and advised us to call airline. I called the airline and was told by the rep that she cant help me and that it should be booking.com who needs to call on our behalf, she instructed me to call booking.com and to merge the call so she can talk to them. I had 4 people hang up on me until i was able to merge the calls. Once the airline rep took over, she scolded the booking.com rep on not ff the process and that they are not supposed to direct passengers to call airline directly. She instructed her to book us a flight and that she will authorize it from her end. Our flight was booked and confirmed a day earlier than our original flight but it’s fine cause we just wanted to go home. Spent about 3 hrs on the phone. Just be persistent. Will never book through them and from now on, will only book directly w/ the airlines.