Remove the chair rail, it just cuts up the space.

One paint color, not two. And remove the chair rail.

And please reconsider using a shade of gray…. You will just look like everyone else.

Consider getting rid of the chair rail, it seems dated since there's no trim below it. Kind of challenging to expect to get color recommendations so quickly here since you want to get paint today. Your flooring and carpet seem slightly on the warm side so consider warms whites. Gray may not be the best choice with your floors.

I am having a hard time envisioning Passive with your floors, which are very nice by the way. Passive is a gray with a blue undertone, which means it's cool. Your floors are warm, and Alabaster is a warm white. Look at Accessible Beige. It will look better with Alabaster and your floors. Although the color has "beige" in the name it does have some gray in it, so maybe it would be a good middle ground for you. Since we don't see anything else in your house such as furniture or rugs it's difficult to make more specific recommendations.

IMO fix the lighting before anything . I like LED 4000K but even 3500K will let you see the colors stay the same all the time . I have no issues with grays I happen to love them but those 2 colors are not right together and honestly remove the chair rail and do one color . I rarely use Alabaster I find it yellow and with your lighting even worse.STOP right now and change the lighting remove the char rail and then figure out the wall colo. I love this for a really nice neutral I cut it 25% usually it works with virtually every other color and will look nice with your trim that seems to be white