Content vanished after "site address (URL) change "

The problem started when I fiddled with the general settings subpanel: https://codex.www.ads-software.com/Settings_General_SubPanel

I was fooling around with the “wordpress address (URL)” and the “site address (URL)” fields (see generic screen shot in link). Originally, they were both pointed to “https://www.example.org/wp/” (as it was set up with the hosting service) and then I switched one of them to “https://www.example.org/” thinking that would move everything back up into the root directory. After doing that I’m no longer able to access the general settings subpanel to change it back, and the majority of the content has disappeared.

If you are able to help, that would be extremely appreciated.

Thanks,