People Blocking their page with PNG's?

I just want to know if blocking your whole profile with a PNG you can't click through is allowed, When visiting these profiles, it is IMPOSSIBLE to remove them or report them!!! Where can I report the usernames? and how can this be prevented?

I have a screen shot of the profile, but I don't want to share it out of respect of privacy!

would be appreciated!

P.S the png is partly transparent, so it's clear they want you to see the profile, but not be able to interact with it 

There is an ability to report any user under the send messages button