What's with the red light from the projector?

The general reason is that the data cable connecting the projector to the computer is loose, and the connector will change if you move it more. Please try it. If there is, you can tighten some screws at the joint to solve it; If not, there may be something wrong with some "pins" of the data cable connector. You can try another data cable. If you can't solve the problem, you can only find after-sales maintenance service.

For reference only, good luck!