Movie Texture not updating

I am trying to play a few movies in succession but they don't seem to be updating the texture. I am able to play scanLoop but when I try to change to login, scanLoop stops but does not change to the other movie texture. Am I supposed to update textures differently? I have tried SetTexture() and trying to change material.mainTexture = newTexture.

I should mention that if I comment out the first yield return, it does play the movie login movie.

 using UnityEngine;
 using System.Collections;
 using UnityEngine.UI;
 
 public class videoPlayer : MonoBehaviour {
 
     public MovieTexture scanLoop;
     public MovieTexture login;
     public MovieTexture Mask;
 
     // Use this for initialization
     void Start () {
         GetComponent<Image>().material.mainTexture = scanLoop as MovieTexture;
         
         scanLoop.Play();
         scanLoop.loop = true;
         StartCoroutine(VideoHandler());
     }
     
     IEnumerator VideoHandler()
     {
         yield return new WaitForSeconds(5f);
         PlayLogin();
     }
 
     public void PlayLogin()
     {
         scanLoop.loop = false;
 
         GetComponent<Image>().material.SetTexture("_MainTex", login as MovieTexture);
         login.Play();
     }
 
     public void PlayMask()
     {
         GetComponent<Image>().material.mainTexture = Mask as MovieTexture;
         Mask.Play();
     }
 
 }