2007 Tahoe Transfer Case not Engaging

My transfer case went out on my 07 Tahoe. I replaced it with a professional rebuilt and also put a new encoder motor on it. The truck says it is in “N” and the light flashes for 2wd for a bit and then goes out. I also have a “Service 4wd” on my display. I have double checked everything ensuring I have the correct transfer case and motor. I am at a loss. Am I missing something? Everything worked good before I lost the bearing in my transfer case. Not sure where to go from here?