Menus frozen & content disappearing

Theme: BoldR Pro 1.5.0

Hello, I’m new here, and to WP in general.

After uploading site to server 3 days ago the widgets menu was frozen but I could work using the accessibility mode.

I noticed yesterday that a page had disappeared completely off the live site. It was sitting with (pending) beside it. Since I dragged it back into place in the menu, the menus page is frozen.

Today, the contents of an ‘Easy Logo Slider’ are gone off the site and off the back end too (content has disappeared!)

The sports club I’ve built the site for are having a launch in 2 days time and I haven’t a clue what’s going on with the site.

Can anyone advise? BTW, I’ve disabled & reactivated all plugins but it doesn’t appear to be the issue.