Hi! Sorry if I'm a bit late, but I feel like I missed something (probably a simple thing, but...)
Under the _physics_process function for the Actor class, you had removed the line "velocity.y = min(speed.y, velocity.y)" somewhere else to within the Player class. Where exactly does it get relocated to? I could not figure this part out.
It gets added to the Player later. In that particular lesson, you just remove it. You'll re-add it in a subsequent lesson.