Zone Coverage Logic Is Broken

I find myself watching replays so often now because I wonder how receivers are being left wide open. Turns out that zones genuinely do not work how they are supposed to. My players will literally get to their spot and stay there even if someone is crossing their face to allow for an easy gain. Or even better, they will run away to a completely different area from their zone. In fact, they will run to where absolutely no offensive players are present and decide to stand there. And you can bet someone is left wide open. Btw im not running match and ive not made any adjustments. This game is absolute garbage.