How do deactivate the plugin when I host access to the site?

I installed the plugin, and got a warning about it not being able to register an SSL certicifate. I am not sure what I am doing really, but I checked the “overide” option in the popup.

Once i did this, i lost access to the site. I believe that this is because it now forwards to the HTTPS url, even though this does not work.

I tried resolving, by deleting the really simple SSL folder in the plugins, as well as the htaccess as I believe that they are recreated (?)

But i still can’t access the site.

Any tips on how to proceed?

The page I need help with: [log in to see the link]