2014 Mazda 3 won’t start

Hello! I'm looking for some advice on how to fix my 2014 Mazda 3. This just recently started where l'll go to turn on the car (push start) and nothing happens. It doesn't crank or anything. The key light illuminates steady green.

I've tried the following: replaced the car battery, replaced the key fob battery, and replaced the brake light switch.After I replaced the fob battery (but before the brake light switch) the car started up and ran like usual for a few days, then randomly stopped starting again today, which is why I tried switching the brake light switch (based on advice I read on another post).

I'm at a loss. I'm not sure where to go from here. It's an intermittent issue. Any advice would be very appreciated.