The earliest recollection of this bug is traced back to PAN-OS 9.1.3 - July 22, 2025. This bug is fixed in PAN-OS versions 9.1.3. Fixed an issue where the firewall failed stateful inspection for GTP forward relocation requests greater than 1,500 bytes and could not parse Access Point Name (APN) information in forward relocation requests. For more information: https://docs.paloaltonetworks.com/pan-os/9-1/pan-os-release-notes/pan-os-9-1-addressed-issues/pan-os-9-1-3-addressed-issues