animation.Play isn't working

Questions & Answers
1

private var zimGO: GameObject; //already found.

    else if(Input.GetKey(KeyCode.S)){			
rigidbody2D.velocity.y = (moveSpeed*-1) * Time.deltaTime;
    				rigidbody2D.velocity.x = 0;
    					zimGO.animation.Play("ZimDown");

Well I’ve look up plenty of things and nothing helps me. I make an animation out of sprites and put it in an animation folder in my assets. Then add the animation to my character. When i press ‘S’ it should play the animation, but it either says it needs to be legacy(if it is it doesn’t change anything) or it just doesn’t do anything.

2

or this one: