IF I POWER ON MODEM BEFORE XR500 I GET NO INTERNET

I cannot power on the modem and complete a normal power cycle before I plug in and turn on my new xr500 router. If I try to complete a normal power cycle as done with literally all routers I will have a 0.0.0.0 IP and no internet.

The only way to make the xr500 work is by turning it on before the modem. 

How can a new router that I bought in may 2020 have this issue connected with it.

For the most part the speeds are fantastic reaching 940 somtimes on a gigabit plan offered by Cox.

But I still have an itch to get the normal power cycle working correctly and wonder how this could be occurring on such a new router.

I looked at other "no internet" threads of which had others also claiming they had to turn on the xr500 router before the modem which turns the entire power cycling fundamentals on its head.

A part of me wonders if I'm not getting the full potential due to a failed normal power cycle.

Does anyone have any ideas?