I wish you and others would stop posting that no one is ever forced. Of course you can call in, but you can't do it every time and expect to not be disciplined.
If the manager sends a text saying that you are working Saturday or Sunday, or if they post a schedule with Saturday or Sunday included, directly ask your Center manager if you are forced. The answer may very well be no.
"All drivers are working Sunday" does not necessarily mean they are forcing. Sometimes they purposely make it ambiguous, and drivers assume they are forced.