Try these steps in order:
On the guest phone
- Turn brightness to maximum.
- Open the ticket from My Tickets, not a screenshot if possible.
- Clean the screen and remove cracked glass protectors over the code.
On the scanner device
- Reload the check-in page and allow camera permissions again.
- Move closer or farther — about one hand-width away often works best.
- Switch to manual lookup if the camera fails. See Manual check-in.
Screenshot: Check-in error state with Try again and manual lookup hint
Invalid code
If the app says Invalid, the ticket may be canceled or for a different event instance. Verify the guest's order in Attendees.