ALTER TABLE DROP COLUMN failed because column 'xxx' does not exist in table 'yyy'

Add a new migration to re-synchronize:

add-migration MissingXXX -IgnoreChanges // tells EF to just take a snapshot
update-database

Now you are back in sync and can continue with future model changes.

OK, finally I solved my problem.
I added field 'xxx' to table 'yyy' manually in my database.