After they make a wish to kill their parents, a group of teenagers discover they?ve messed with an entity that makes this wish come true.

I think it's better to have a protagonist and also what is the conflict of your story? Is this entity bad or good? because they make a wish and he makes it come true.

But he wished it in the first place... He gets what he wants. Was it a joke wish and he realises that only after making the wish? If so, you need to specify that in the logline.

What are his goal and action? Assuming he doesn't really want his parents dead, what does he do to stop the killing?

"When a wish goes horribly wrong, a rebellious teen must team with his friends to take down an evil genie before the entity kills his parents."