Brake Lights

Hi!

I am new to the forum. Been reading a lot of posts and it seems like a nice community.

I been searching up and down for brake light info. My driver side tail light is illuminating when I have the auto switch on, but the brake light does not work when I press on it. My passenger one lights up when brake is pressed. Any suggestions as to what it might be, also what I should do?

2012 Prius. 73K miles.

I have not had any issues with the vehicle. It’s been good to me. I checked fuse box, it was good, and not really sure because I found out it does not have bulbs like other vehicles..