I'm going to guess that the throwing arm & launch plate are not parallel through the arm's travel. Our club had this problem with a new Supermatch six. Look at the rub strip on the arm & see if you have target paint the same width for the full length. This is how we figured out our problem.
Disconnect the throwing spring so you can rotate the arm through its travel. Check that the arm contacts the target at the same height for the full length of the arm. There are recessed machine screws on the launch plate to adjust the plate. The Bowman web site has no info on what clearance between the arm & target. The Promatic site does. Use the Promatic info, the target won't know the difference.
I hope this helps.
Bob.