Shared internet connection blocks certain website

[GodAtum]

I'm getting this error when accessing certain websites, but not others. My internet is going through a shared educational connection. I suspect the IT dept are doing a Man in the middle and inspecting everything doing through. Is this even fixable?

 

[GodAtum]

I'm only there for a conference this week so not much point in contacting IT. Just a bit annoying as my own personal Nextcloud server doesn't connect but Google does.