Event date cannot be in the future.
Use the day the event happened; keep upcoming work in a reminder.
Why does this happen?
Event date is later than today according to your phone’s clock.
How do I check it?
Check the year, month and day in Event date against your farm record. Also check that your phone shows today’s correct date.
For a completed event, enter its actual date. Put an upcoming task in a separate reminder. Use Follow-up date for a later check on a completed event.
Choose Save for the completed event, then check its date and any follow-up reminder.
How do I verify the result?
The event history shows the completed event; the reminder holds the planned task.
How do I keep my records safe?
Keep planned work as a reminder until it happens.