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If your invitation has expired, you must contact the person who originally invited you and request that they follow the steps outlined below.
If a user you invited reports their invite has expired, as the inviter:
Go to the manage invites page.
Cancel the expired invitation.
Resend a new invite.
If a new user’s invite expires, as the inviter go to the manage invites page. From there you must first cancel the expired invitation and then resend a new invite.