Admob Memory Issues

In my game, I added in ads using AdMob. I have a banner and interstitial ad. Everything works fine on android, but when I use IOS, the entire game will start lagging and it will crash. I get the error in Xcode: terminated because of memory issue.`using System.Collections; using System.Collections.Generic; using UnityEngine; using UnityEngine.SceneManagement; using GoogleMobileAds.Api;

public class DestroyPlayer : MonoBehaviour {

 float deathCooldown = 5;

 public bool dead;

 public int value = 1;

 public int yay = 3;

 public AudioSource saw;

 bool playSawSound = true;

 public int index;

 public GameObject deathMenu;

 public int adShow;

 public InterstitialAd interstitial;

 void Start () {

     saw = GetComponent <AudioSource> ();
     index = Random.Range (1, 5);
     adShow = Random.Range (1, 3);
     RequestInterstitial ();

 }


 void OnCollisionEnter (Collision  col)
 {
     if (col.gameObject.tag == "cup") {
         ScorePoints.score += value;
         Destroy (this.gameObject);
     }
     if (col.gameObject.tag == "Death") {
         dead = true;
         RequestInterstitial ();
     } else {
         dead = false;
     }
         
         
 }


 void Update()
 {
     if (dead == true) {
         if (playSawSound) {
             saw.Play ();
             playSawSound = false;
         }
         deathCooldown -= yay * Time.deltaTime;
         GameObject.Find ("Cups").GetComponent <CupMovemnt> ().cupVelocity = 0f;
         if (deathCooldown <= 0) {
             

         }
         if (adShow == 1) {

             if (interstitial.IsLoaded ()) {
                 interstitial.Show ();
                 interstitial.Destroy ();
             }
         }
         GameObject.Find ("Canvas1").GetComponent <Canvas> ().enabled = true;

     }

 }

 public void RequestInterstitial()
 {
     #if UNITY_EDITOR 
     string adUnitId = "unused";
     #elif UNITY_ANDROID
     string adUnitId = "xxxxxxxxxxxxxxxxxxxxxxxxxx";
     #elif UNITY_IPHONE
     string adUnitId = "xxxxxxxxxxxxxxxxxxxxxxxxxx";
     #else
     string adUnitId = "unexpected_platform";
     #endif

     // Initialize an InterstitialAd.
     interstitial = new InterstitialAd(adUnitId);
     // Create an empty ad request.
     AdRequest request = new AdRequest.Builder()
     .Build();
     // Load the interstitial with the request.
     interstitial.LoadAd(request);
 }
     

 /*void restart () {
     //if (dead == true) {
         //GameObject.Find ("Canvas1").GetComponent <Canvas> ().enabled = true;
     //}
 //}*/

}

That had my interstitial ad stuff in it. Now here is my banner ad code: `using System.Collections; using System.Collections.Generic; using UnityEngine; using GoogleMobileAds.Api;

public class AdManager : MonoBehaviour {

 void Start () {
     RequestBanner ();
 }

 void RequestBanner()
 {
     #if UNITY_EDITOR
     string adUnitId = "unused";
     #elif UNITY_ANDROID
     string adUnitId = "xxxxxxxxxxxxxxxxxxx";
     #elif UNITY_IPHONE
     string adUnitId = "xxxxxxxxxxxxxxxxxxx";
     #else
     string adUnitId = "unexpected_platform";
     #endif

     // Create a 320x50 banner at the top of the screen.
     BannerView bannerView = new BannerView(adUnitId, AdSize.Banner, AdPosition.Bottom);
     // Create an empty ad request.
     AdRequest request = new AdRequest.Builder()   
     //.AddTestDevice(AdRequest.TestDeviceSimulator)       // Simulator.
     //.AddTestDevice(SystemInfo.deviceUniqueIdentifier)  // My test device.
     .Build();




     // Load the banner with the request.
     bannerView.LoadAd(request);



     }
 }