Contact won’t stay Pinned

Updated to iOS 18 a few days ago. Yesterday I noticed that a specific contact was no longer Pinned in my messages. I pinned it back. Every time I leave the message app and return the contact is unpinned again. I pinned it back. Restarted / hard shut down my phone and it will not stay pinned. Keeps unpinning once I leave the app. It is only with one specific contact. The contact is pinned on other iPhone devices that have a different iCloud. The issue does not happen with other contacts. I have tried pinning random contacts and they all stay pinned. The contact also has iOS 18, on an iPhone 11. I am having this issue on my iPhone 13 Pro Max.