Guests Can’t Comment Despite Settings Allowing It

Issue:
Suddenly, guest users are required to register before commenting, even though all settings appear to allow guest comments.

WordPress Settings:

• Users must be registered and logged in to comment — Disabled

• Comment author must fill out name and email — Enabled

WPDiscuz Settings:

• Allow guests to comment — Enabled

Troubleshooting Steps Already Taken:

• Disabled all plugins — No effect

• Updated WordPress to the latest version

• Updated Newspaper theme to the latest version

Current Result:
Guests are still being asked to register or log in before they can comment.

Additional Info:

• Theme: Newspaper

I'd appreciate any suggestions or insights on what might be causing this. Could it be theme-related, or is there a hidden setting somewhere I might have missed?

Thank you