Nextcloud can't connect

    After I input my ip in the Nextcloud and try to connect to my server, I input my authentication and it says success. But my Nextcloud couldn't continue and shows like below:

    It says the server rejects visit, but I click the link and it's ok to log on. What's wrong?

Btw, I completely follow the instruction from here: http://blog.filerun.com/how-to-install-filerun-on-centos-7/

and the FileRun runs well in the Chrome. My server is from Vultr.

    Looking forward to your reply!