Could be the sights are off, but more likely you are pulling to the left due to either/or your grip or finger position on the trigger. I’m assuming you are right handed. This is a pretty common occurrence, though even more common is low/left.
When you grip the gun, you should see a pretty straight line between the barrel and your forearm. In other words, your wrist needs to be straight. Typically not enough finger on the trigger can cause left hits. If you are using the tip of your trigger finger, try the pad of the next joint. If this takes you to the right, try something in the middle.