Boolean issues

Hi, I currently have the problem that I'm able to activate the "yellow color" and change to "pink" but not the other way around so hopefully someone here is able to point me in the right direction :)

 using UnityEngine;
 using System.Collections;
 
 public class ColorControllerScript : MonoBehaviour {
     
     public GameObject LightPinkBox;
 
     
     public GameObject LightYellowBox;
 
 
     public GameObject LightBullet1;
     public vp_HitscanBullet script;
 
 
 
     
     public Texture splat1;
     public Texture splat2;
     public Texture splat3;
     
     // Use this for initialization
     void Start () {
         
         LightBullet1.renderer.sharedMaterial.mainTexture = splat1;
         LightBullet1.renderer.sharedMaterial.color = Color.green;
         script = LightBullet1.GetComponent<vp_HitscanBullet>();
     
         }
     
     
     
     // Update is called once per frame
     void FixedUpdate () {
 
         ChangeColor();
 
     }
 
     void ChangeColor()
     {
         
         if(LightYellowScript.FromGreenToYellow==true)
         {
             print("Can change to yellow");
             LightBullet1.renderer.sharedMaterial.color = Color.yellow;
             LightBullet1.renderer.sharedMaterial.mainTexture = splat3;
             
             
         }
         if(LightPinkScript.FromGreenToPink==true)
         {
             print("Can change to pink");
             LightBullet1.renderer.sharedMaterial.color = Color.red;
             LightBullet1.renderer.sharedMaterial.mainTexture = splat2;
         }
 
     }
 }