error The getter 'month' was called on null.

I have this problem when I try to refresh something from the table:

Exception has occurred.
NoSuchMethodError (NoSuchMethodError: The getter 'month' was called on null.
Receiver: null
Tried calling: month)

In my application I have a lot of users, and a calendar for each user (to put the day they enter).

i try using a single CalendarController () or make a fixed list to have a CalendarController for each one, but when I want to modify something I get the error that a month, I get null, for example, I have another calendar that would filter by days (to see which people entered that day). and the initial day works great, changing it I get this error. It also happens to me with the hot restart.

any clue? the calendar works great, i have the days of the firebase, and work fine. but filtering or refreshing have this problem.

The report names no repository file, test, or reproducible entry point. Start by reproducing the calendar refresh and filtering flow described, using the CalendarController and Firebase-backed dates, then identify where the null month is read. Done means the cause is confirmed and the behavior is covered by a regression test or documented fix.

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