My two iPads won't sync Safari tabs even though they use the same Wi-Fi and iCloud

2 iPads both IPad IOS 18 and running version 18.5 will not sync on Safari . Both connected to same wifi, same account and both switched on in iCloud. One is 2019 iPad Air (3rd gen) and the new one is iPad Air M3 2025 13". Have also restarted both devices as explained on the internet but still no success. Any help would be greatly appreciated.

[Re-Titled by Moderator]

Original Title: Safari on 2 iPads not syncing