Joystick problems Unity 3D Mobile

Hello, I'm making slither.io mobile in unity 3d and my joystick controls don't work. The snake only moves left and right. I want it to follow the direction the joystick is pointing. Help me please. Please write very clearly as I am new to this. And sorry for my bad english. I hope, you understood me

My script:

using System.Collections; using System.Collections.Generic; using UnityEngine; using UnityEngine.UI; public class SnakeMovement : MonoBehaviour { public float Speed; public float RotationSpeed; public List tailObjects = new List(); public float z_offset = 0.5f; public GameObject TailPrefab; public Text ScoreText; public int score = 0; public Joystick joystick; void Start() { tailObjects.Add(gameObject); }

 void Update()
 {
     ScoreText.text = score.ToString();
     transform.Translate(Vector3.forward*Speed*Time.deltaTime);
     Vector3 direction1 = Vector3.up*joystick.Horizontal;
     transform.Rotate(direction1*RotationSpeed*Time.deltaTime);
 }
 public void AddTail()
 {
     score++;
     Vector3 newTailPos = tailObjects[tailObjects.Count-1].transform.position;
     newTailPos.z -= z_offset;
     tailObjects.Add(GameObject.Instantiate(TailPrefab,newTailPos,Quaternion.identity) as GameObject);
 }

}