What A mess--new network--unable to connect to ROCK now

Oh boy–what a mess

will do my best to describe what I barely understand.

I replaced my Modem and have a new network.

I am unable to connect to my NUC (ROCK) via my controller (IMAC and Android phone app)

I tried to start over and uninstalled ROON and re installed but it just tells me “looking of your ROON core”

I suspect it is still on the old network that no longer exists?

Im not sure how to assure my ROCK is connected to my new network.

Any help is appreciated