回複：下載了該說明書，把Lansetting 中Tenda router 從192.168.2.1改成 192.168.0.2,

Try this:

Cisco router LAN side DHCP setting:

See if the Starting IP Address is 192.168.0.2.  If yes, change it to, say, 192.168.0.10.

=================================

You probably have a PC or other device occupying 192.168.0.2