The connection of the site was ridiculous. 
I and my friend tried to visit my site through different WIFI network but failed. The connection time was out and no response was shown. The website could not be shown in PC.
However, we tried phone. The network could be shown in mobile using phone data, but failed in using WIFI network.

Some of my clients were able to visit the site through PC but not mobile site.

This is ridiculous. Could anyone help me settle the problem? Am I using a wrong site setting ?

Thank you very much!