UCE001 ';' expected, Insert a semicolan at the end Even though I already have one

Here is my script, i still can’t get the hit detection to work, and now I am having this problem.

using UnityEngine.SceneManager;

function OnTriggerEnter (col : Collider) {

            Debug.Log(col.gameObject.name);
            if(col.gameObject.name == "Key");
            {
                
                SceneManager.LoadScene(0);
            }
        }

In java script use:

import UnityEngine.SceneManagement;

Instead of

 using UnityEngine.SceneManager;

Plus your IF statement is also having a semicolon at the end