Good morning and thank you for posting in the Final Fantasy XIV Technical Forums.

Just to clarify a bit more on the situation, are the cookies and cache cleared from the PlayStation 5? (Settings > System > Web Browser)
Are Final Fantasy XIV and the PlayStation 5 fully updated?
Have you attempted to power cycle the router(s)/modem(s)? (Unplugging the device and leaving it idle for 10-15 minutes)

If you are experiencing issues with the PlayStation version of Final Fantasy XIV, please try the following:
■ Perform a system update on your PlayStation®5
Perform the most recent system update and then try a version update for FINAL FANTASY XIV Online.
PlayStation®5: The update can be performed from the home menu by selecting
[Settings] → [System] → [System Software] → [System Software Update]

■ Remove peripheral devices to create a simpler environment for the program to run
Remove any peripheral USB devices (gamepads, cameras, microphones, headsets, etc.) to create a more stable, simple environment for your console to run the game. Also consider inserting the devices to different USB ports or removing and reinserting them.

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