Hi,
Recently my ps4 pro stopped reading discs.
If I set the ps4 vertically it will read discs again, so I figured I had to replace the laser.
After replacing the laser is still wont read discs in the horizontal position.
What else could it be? Did i get a bad laser?
The laser might be just out of alignment, maybe try taking it apart again and give it another shot to make sure the laser is perfectly centered in it housing and also make sure the lens is clean.
Check alignment and also laser ribbon cable.