This situation is normal, and there is no need to check the reasons of customers, because you can visit other websites, but you can't visit this one. This happens because the server side of this network shields the IP address of the client and prohibits the client from accessing it, because the IP address of the client may endanger the behavior of the server. Like uploading a Trojan horse.

The solution is to ask the server to unlock the IP or the client to change the IP address line.

The actual situation is as follows.

The address cannot be browsed.

Check the local IP address, (there is no proxy IP below)

After changing the IP address of the agent, you can browse the webpage that showed the error before (as shown below).

Another possibility is that individual router versions are outdated. For example, the router used by Swift FW 150R in Shenzhen Youjialian was replaced by TP TL-WR886N equipment, which solved the above problems.