Send it back. Even if there is some radical mounting height mismatch between the slide and the sight, that amount of error doesn't make sense.
I'm probably in the minority but I stick with the trijicons for this. They are getting b**chslapped at high speed every time the slide cycles. Robust electronics and anal QC costs money, unfortunately. I know some people have decent luck with the cheaper red dots but I think there is a bit of a rolling the dice aspect involved.
