Hi @芷薇0,
Too bad you can't stay at the place selected< i hope you still have a good trip!
To prevent disappointment on both sides, Airbnb has some rules in place to minimise the number of cancellations. It's important that you are familiar with all the rules that come with booking through this platform, because I'm sure the host has done so.
The penalties for cancelling are far more severe for a host, that's why you were asked to cancel instead of the other way around! I see that you are a host yourself, even more important that you are aware of this!
Get in touch with Airbnb, for more details click here If you have proof in the Airbnb chat that this sneaky host asked you to cancel even though they messed up their availibility, you might be able to get this reversed.
Good luck!