Local ip changed

Hi today morning I found my node turn to offline. My local ip was change, so the port is closed. I try to set the ip in my os but it’s denied. so I go to my Asus router set like this, it’ work but I am not sure it is all fine.

I have a modem hold by ISP. yesterday I set a DMZ mode inside, I didn’t change any thing in the modem. Now is online, the working log is here. I just check if there is a setting problem which I didn’t know Thank you

Usually routers have an ability to assign a static IP to your PC, if you map the MAC address of the PC with the local IP.
Your current configuration of DHCP with only one IP will not allow any other device to work in your network.