Why won’t my rear camera and flash light work?

I installed a new screen that also already had the front facing camera and speaker. Everything is kosher except for now when I try to use my rear camera, the screen remains black with a symbol signaling that the flash is disabled as well. The front facing camera works just fine. I’ve installed many screens before but never with the small components. I’ve played with the possibility of transferring the original front camera and speaker, but would rather not mess with it if it’s not a viable solution.