“This link is no longer valid”
Links rotate on resends and die when the card seals — here’s the decode.
Three normal reasons:
- A newer message exists — reminders and resends rotate the link; older copies stop working. Use the newest message, or ask the organizer for a fresh link.
- The card sealed — the signing window closed and delivery is on its way.
- The card was withdrawn — the organizer discarded it or the event was removed.