Instantiate when Online or Offline.

Hello I wanna make a zombie spawned and spawned differently if the player is on a server or not online. But It only makes 1 not any more so please Help Heres my code.

using UnityEngine; using System.Collections;

public class ZombieSpawner : MonoBehaviour {

 public Transform _Zombie;
 
 public bool HasZombieSpawnedOn = false;
 public bool HasZombieSpawnedOff = false;
 
 public float SpawnTimer = 0;
 
 public GameObject ZombiePrefab;
 
 public void Update(){
     
     
     if(Network.isServer){
         SpawnOnlineZombie();
     }
     else{
         SpawnOfflineZombie();
     }
     
 }
 
 public void SpawnOnlineZombie(){
     if(HasZombieSpawnedOn == false){
     SpawnTimer += Time.deltaTime;
     
     if(SpawnTimer >= 1){
     HasZombieSpawnedOn = true;
     GameObject SpawnedZombie = Network.Instantiate(ZombiePrefab, Vector3.zero, Quaternion.identity,1) as GameObject;
     SpawnedZombie.transform.position = gameObject.transform.position;
     SpawnTimer = 0;
     _Zombie = SpawnedZombie.transform;
         
     }
     if(_Zombie == null){
         HasZombieSpawnedOn = false;
     }
     }
 }
 public void SpawnOfflineZombie(){
     if(HasZombieSpawnedOff == false){
     SpawnTimer += Time.deltaTime;
     
     if(SpawnTimer >= 1){
     HasZombieSpawnedOff = true;
     GameObject SpawnedZombie = Instantiate(ZombiePrefab, Vector3.zero, Quaternion.identity) as GameObject;
     SpawnedZombie.transform.position = gameObject.transform.position;
     SpawnTimer = 0;
     _Zombie = SpawnedZombie.transform;
         
     }
     if(_Zombie == null){
         HasZombieSpawnedOff = false;
     }
     }
 }
     
     

}