material.SetTexture reset

I’m working on a project (I’ve finished my “Hide and Seek” one) and am working on a fighting game like smash bros. i have gotten the character (For now a goku sprite) and have gotten it to look one way when moving, and the other, but when the key is released. they stay the way they are. if i use

if(Input.GetKeyUp(KeyCode.Key))

it makes a grey box covering my character.

My current script:

using UnityEngine;
using System.Collections;

public class GokuAnimate : MonoBehaviour {
	
	public Texture gokuMove;
	public Texture gokuMoveL;
	public Texture gokuStand;
	
	void Update () {
		if(Input.GetKeyDown(KeyCode.D))
		{
			renderer.material.SetTexture("_MainTex", gokuMove);
		}
		
		if(Input.GetKeyDown(KeyCode.A))
		{
			renderer.material.SetTexture("_MainTex", gokuMoveL);
		}
		
	}
}

The issue was a corrupted Image