Good day to you djflaksdjflksdjflskadkjflsd,
Could you please clarify for us, are you attempting to share a calendar or add invitees to an event?
If you’re sending an invite to an even, are these the steps you’re following? Send invitations in Calendar on iPhone
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 the plus sign to select Contacts.
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.
4. 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.
Note: With Microsoft Exchange and some other exchange servers, you can invite people to an event even if you’re not the one who scheduled it.
When you view an event that you want to add someone to, or you’re looking at the calendar you want to share, is it an event or calendar that is syncing with whichever account you sync with? That might be iCloud or another service.
Thanks.