There are many reports in the Google Webmaster Help forum and on social media, like Twitter of webmasters complaining that the Google Search Console is not loading. Instead, it is returning a 404 - page not found server status.
It may be that the Google Search Console is overloaded right now for some regions? I am personally and currently on a flight and it is loading fine for me.
But there are enough complaints in the forums and on social media to know there is a wider issue.
Here is a screen shot from one webmaster:
Do you have the same issue?