Initially impressed now not sure - Nikon P-Tactical Superdot 2 MOA Red Dot Sight

Initially I was impressed with this optic. It was clear and bright, easy to mount and operate. It zeroed quickly at 25 yards and then I moved to the 100 yard range where using ballistics, impact should have been very close to bullseye. First shot was acceptable right so a minor adjustment was made, I thought! Next shots were 4-5” high left and not consistent. I tried to adjust back right and was completely off paper. Mount was solid and tight. Back to 25 yard range and start over. Not sure what happened but adjustments do not seem good. Not sure if it’s just this unit and needs replacement or the model overall.