it could be a number of things....
center shot or knocking point needs adjusted in or out...or up or down. your arrows could be spined wrong for your set-up...kinda hard to diagnose what you're asking because you've left it open to a large range of problems....
best thing to do is shoot it through paper first. come back on here and let me know what kinda tear you have in the paper. straight left, straight right, straight up, straight down...etc...etc...etc