Iphone Calendar Invitation Cannot Be Sent. How to fix calendar invitation cannot be sent on iphone issue; If you are encountered with ‘calendar invitation cannot be sent’ error on your iphone or ipad, you can refer the below mentioned troubleshooting methods.
To fix your response to the invitation cannot be sent error, try resetting the calendar app or update your ios to the latest version. On your ios device, ipad or iphone, tap settings > your name > icloud toggle off “calendars” wait a few minutes;