Not sure where to post this. Didn't see a category for scopes so here we go. I recently got around to purchasing a red dot for my Glock model 40. I bought a Vortex Venom red dot. I own several Vortex products and never an issue. Got the red dot mounted on the gun and anew battery installed with the cap on right and it tightened. When I turn the red dot on it stays on for maybe five seconds and turns off. This happens every time I turn it on. Has anyone else have had this happen?