There are several things that can cause a light reflection to appear in your photos.
1. Make sure that the booth's door is completely closed, so no light can come in from the backside of your booth.
2. Make sure no other light leaks from any other direction to the inside of the booth (for example, if you own the Mirror Me Booth. the hole at the top of the booth, where the wires connected to the flash are going through, can be a source of such a light leak).
3. Make sure your camera is on M mode (on the dial) and that its built-in flash is disabled.
4. Change the angle of your camera, tilt it down\up as needed.
5. If your strobe flash is external to the booth, change its angle (or the umbrella's, if you're using one).
*If you're using an umbrella, make sure it faces to the right direction, as shown in the picture:
6. Disable the flash and increase the ISO on the camera to test if it’s the flash causing it.
7. Make sure there is no direct light pointing at the screen. Change the position of your booth if needed (there might be something bright in the background that bumps the light back to the screen).
8. If you have any LED lights inside the booth (the TV’s for example), try to cover them with black tape.
9. If the above doesn't help, cover the white text on the inner side of your camera's lens (you can cover it with a black marker or duct tape).
10. If the issue is your LED ring light reflection: Make sure you have a LED Ring Stop Ring Feature state before the DSLR feature state: