Question cant get input to work

so I'm trying to make a gun in unity and i want it so if i push a button on the controller it will drop the mag. i cant seem to figure out a way to detect input. can i get some help with getting input

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4. using UnityEngine.UI;
5. using UnityEngine.XR;
6. using UnityEngine.XR.Interaction.Toolkit;
7.  
8. public class gunmagholder : XRSocketInteractor
9. {
10.  
11.     public parentgrabbable gun;
12.     private parentgrabbable mag;
13.     private XRBaseInteractable Magezene;
14.     public gunmagholder script;
15.     private Rigidbody rb;
16.     private XRController controller;
17.     private bool getGameobj;
18.     public bool cangrabout;
19.     public Text debugger;
20.  
21.     protected override void OnSelectEntered(XRBaseInteractable interactable)
22.     {
23.         mag = interactable.GetComponent<parentgrabbable>();
24.         rb = interactable.GetComponent<Rigidbody>();
25.         Magezene = interactable;
26.         if (mag != null && cangrabout == false)
27.         {
28.             mag.enabled = false;
29.         }
30.     }
31.  
32.  
33.     protected override void Start()
34.     {
35.         debugger.text = "test";
36.     }
37.  
38.  
39.  
40.     void Update()
41.     {
42.         if (gun.isSelected && cangrabout == false) {
43.             if (controller.inputDevice.TryGetFeatureValue(CommonUsages.secondaryButton, out bool button))
44.             {
45.                 magdrop();
46.                 debugger.text = "button pressed";
47.             }
48.         }
49.  
50.         if (gun.isSelected && getGameobj == false)
51.         {
52.             getGameobj = true;
53.             controller = gun.selectingInteractor.GetComponent<XRController>();
54.             debugger.text = "got controller";
55.         }
56.         else if (gun.isSelected == false)
57.         {
58.             getGameobj = false;
59.             controller = null;
60.         }
61.     }
62.  
63.  
64.     void magdrop()
65.     {
66.         script.allowSelect = false;
67.         mag.enabled = true;
68.         rb.AddForce(0, -1, 0);
69.         Invoke("EndMagDrop", 3);
70.     }
71.  
72.     void EndMagDrop()
73.     {
74.         script.allowSelect = true;
75.         rb = null;
76.         mag = null;
77.         Magezene = null;
78.     }
79. }
80.