Unassigned GameObject on Client

So I have followed quill18’s tutorial on multiplayer which worked perfectly. I then tried to add my own features, in this case, I added a myUnit. When I tested it , it works fine on the server side, but on the client it didn’t. Here’s a snippet

    void Start () {
        		
        		//Is this actually my own local PlayerObject?
        		if( isLocalPlayer == false){
        				return;
        		}
        		CmdSpawnMyUnit();
        		CmdSpawnMySphere();
        	}
        
        public GameObject PlayerUnitPrefab;
        public GameObject myUnit;
        	[Command]
        	void CmdSpawnMyUnit(){
        		//We are guaranteed to be on the server right now.
        		GameObject go = Instantiate(PlayerUnitPrefab);
        		//selectedUnits.Add(go);
        		myUnit = go;
        		//Now that the object exists on the server, propagate it to all
        		//the clients(and also wire up the Network Identity)
        		Debug.Log("Player Object :: --Spawning Unit");
        		NetworkServer.SpawnWithClientAuthority(go,connectionToClient);
        		Debug.Log("Player Object :: --Unit Spawned");
        
        	}

public GameObject spherePrefab;
public GameObject sphereUnit;

		[Command]
	void CmdSpawnMySphere(){
		//We are guaranteed to be on the severe right now.
		GameObject go = Instantiate(spherePrefab);

		sphereUnit = go;
		//Now that the object exists on the server, propagate it to all
		//the clients(and also wire up the Network Identity)
		Debug.Log("Player Object :: --Spawning Sphere"); 
		NetworkServer.SpawnWithClientAuthority(go,connectionToClient);
		//cam = go.GetComponent<Camera>();
		Debug.Log("Player Object :: --Sphere Spawned");
		//Debug.Log("cam = " + cam.name);
	

	}

}

The error message says

“UnassignedReferenceException: The variable myUnit of PlayerObject has not been assigned.You probably need to assign the myUnit variable of the PlayerObject script in the inspector.”

myUnit was not assigned when played on a client but on the server it works how it is supposed to. Meanwhile, there is no problem with the sphere, I can control them both server and client side. Any help would be appreciated.

Can you provide us a stacktrace please? Where this error occurs? Are you sure that there are no calls to this gameObject before it has been initialized? Is there any more code that you can provide to us?