A QuickLink can expire, be revoked, or no longer have permission to pair the intended number. A real-number link also depends on the team's Pay-As-You-Go access and funding when pairing starts. Creating the link does not reserve permission or credits indefinitely.
Ask the sender to check the link's status and create a replacement if needed. Open it only for the intended phone owner. If a fresh valid link fails, report the visible error and time. Do not paste the full private link, QR code, or pairing code into a ticket.