Admin page not found after changing WordPress and Site Address in General Settin

I’m not very familiar with WordPress and was trying to change a clients page to not automatically redirect to the /wp2 sub directory and instead run the index.html in root like normal in cPanel.

The guide I was following suggested removing the /wp2 from the WordPress Address (URL) and Site Address (URL) under General Settings on WP Admin.

But as soon as I did that the page started giving 404 errors.

I’ve tried forcing the default theme, and disabling plugins like other guides suggest but so far no luck.

Any suggestions?

Thanks.

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