Site Blocked warning from neuster won't let me open a particular site. How can I get the protection removed?

A site that I've been accessing for years (welovetotravel.club) now comes up with a Site Blocked Warning from neuster. It happens on Safari, Chrome, and FireFox.

I called my internet provider (Spectrum). They said Apple needs to remove the protection on that site. I am able to get to the site on my iPhone using cellular instead of WiFi so it would not be relying on Spectrum, but had trouble with the password so I clicked Forgot My Password and it said it was sending me an email requesting password change but I never got an email after several tries. When I called We Love To Travel, they said they were sending me some emails, but they never came. Can Apple be blocking emails from them?