Why nothing happens if a Box Collider enters a Trigger?

I have 2 objects: a Box Collider (controllable with the arrow keys) and another Box Collider which is set on “Is Trigger”.

The Trigger Box Collider has attached a script:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class isWall : MonoBehaviour {
    void OnTriggerEnter2D(Collider2D collision)
        if (collision.tag == "Wall_Verifier")
            Debug.Log("It's a wall :)");

In theory when the Box Collider (called “Wall_Verifier”) enters this Trigger, the console should print “It’s a Wall”, but, in reality, nothing happens!

I even tried to put this piece of code inside the script attached to “Wall_Verifier”, the result is the same as above.

Where’s the error?

You say that the Box Collider is called “Wall_Verifier”,but is it also tagged as “Wall_Verifier”?

It was something that had to do with the rigidbodies, I attached to “Wall_Verifier” a Rigidbody2D and now it works