calendar keeps changing location for flights

Hi Renee,

Have you already confirmed that no one with access to the note is making any updates to the event? Even small changes to the event can bring up this alert. Here's some information about how to send invites and manage your notifications for them:

"Invite others to an event

You can invite people to an event you’ve scheduled.

1. Tap the event, then tap Edit near the top of the screen.
2. Tap Invitees.
3. Enter the names or email addresses of people you want to invite, or tap  to select Contacts.
4. Note: For you to send a calendar invitation to a contact, they must have an email address. See Add and use contact information on iPhone.
5. Tap Done.

If you don’t want to be notified when someone declines a meeting, go to Settings  > Calendar, then turn off Show Invitee Declines."

You can take a look at the full resource here: Send invitations in Calendar on iPhone

If things persist we'd recommend reaching out for additional support here: Get Support

Take care.