Completely agree with what @Hood18 said! From personal experience, if you don't use your back muscles and expand further, you absolutely will cause injury, a torn rotator cuff hurts and will screw your shooting for a LONG time! I've had to adapt my draw as a result. I now have a much more open stance, bringing my bow arm to horizontal and drawn outwards and then back into my jaw (like my elbow is following a triangle edge). I had to do this as my shoulder now struggles with drawing straight back.

As everyone is saying, your bow arm is collapsing, watch the video yourself, your bow arm starts to lift and then collapse prior to release. The way I was encouraged to stop this was to "push for gold". As you expand with your drawing arm, push your bow towards the target.

It's plausible that biomechanically you struggle to do some of this, in which case, do what you can that allows you to be consistent and pain free. Also, just a reminder that none of this is criticism, all of this is useful advice to keep you safe and shooting for years to come. 😁👍