The most likely thing is that the centershot adjustment is off, too far to the left. There should be a thread on walk back tuning somewhere on this site. Someone with lots of quality experience can explain it much better than I can, but that is likely what is wrong. Might have been a little too hasty setup, or the rest moved, or maybe even your sight moved to the right.
Check everything for tightness, then walk back tune. Good luck getting it fixed.