How to get isGrounded to work

So I am trying to be able to jump but with my ground detector, I cant!

Here is my movement script it also has other thing like sprinting(which also doesnt work for the same reason) I am using an empty gameobject as the GroundDetector

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 namespace Com.Kawaiisun.TRANESON
 {
     public class Movement : MonoBehaviour
     {
 
         //public
 
         public float Speed;
         public float sprintModifier;
         public float JumpForce;
         public Camera PlayerCam;
         public Transform GroudDetector;
         public LayerMask Ground;
 
         //private
 
         private Rigidbody rig;
         private float BaseFOV;
         private float SprintFOVModifier = 1.5f;
 
         private void Start()
         {
             BaseFOV = PlayerCam.fieldOfView;
             Camera.main.enabled = false;
             rig = GetComponent<Rigidbody>();
         }
 
         void FixedUpdate()
         {
             float t_hmove = Input.GetAxisRaw("Horizontal");
             float t_vmove = Input.GetAxisRaw("Vertical");
             bool sprint = Input.GetKey(KeyCode.LeftShift) || Input.GetKey(KeyCode.RightShift);
             bool jump = Input.GetKeyDown(KeyCode.Space);
 
             bool isGrounded = Physics.Raycast(GroudDetector.position, Vector3.down, 0.1f, Ground);
             bool isJumping = jump && isGrounded;
             bool isSprinting = sprint && t_vmove > 0 && !isJumping && isGrounded;
 
             if (isJumping)
             {
                 rig.AddForce(Vector3.up * JumpForce);
             }
 
             Vector3 t_direction = new Vector3(t_hmove, 0, t_vmove);
             t_direction.Normalize();
 
             float t_adjustedSpeed = Speed;
             if (isSprinting) t_adjustedSpeed *= sprintModifier;
 
             Vector3 t_targetVelocity = transform.TransformDirection(t_direction * t_adjustedSpeed * Time.deltaTime);
             t_targetVelocity.y = rig.velocity.y;
             rig.velocity = t_targetVelocity;
 
             if (isSprinting) { PlayerCam.fieldOfView = Mathf.Lerp(PlayerCam.fieldOfView, BaseFOV * SprintFOVModifier, Time.deltaTime * 8f); }
             else { PlayerCam.fieldOfView = Mathf.Lerp(PlayerCam.fieldOfView, BaseFOV, Time.deltaTime * 8f); ; }
         }
     }
 }