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Double check the email address
Open the Contact’s details on the Contacts screen and double-check their email address.
💡 Email addresses cannot be changed. If you need to fix the email address, remove the contact and create a new one.Resend the Invite
Up until a contact accepts the invite, you will see an “Invite Sent” message and Resend button shown next to the Contact details. You can click this button to have the invite email resent to the contact. As soon as the contact accepts the invite and signs up, this message will disappear.
Check Spam folder
If all else fails, have the contact check their Email spam folder just in case the invite email was somehow incorrectly filtered.