*Help* Static IP address worked once, but no more

I set a static IP address and tested it using the web UI, completed the test, made sure it was working, and confirmed the change. The computer I have TrueNAS installed on also points to the new IP address. But now, a day later, it no longer works. Does anyone have any suggestions on how to troubleshoot this?

Thanks for any help

You have to set it inside your modem, which is likely using DHCP. Personally, I irresponsably set the DHCP lasting time to infinite and beyond.

Thanks for responding, how do I set it inside my modem?

Well, that depends on your modem. Usually, you can find specific guides online.

I believe I found it, it has the option to change from DHCP to Reserved IP, would this be correct?

Yup.

Two weeks for me. Seems to be a happy medium.