Spaceship Braking doesnt work,Spaceship Brakeing

My brake System doesnt work (It is the same reaction, if i remove the brake part of the code) The Brake System is the last part of the code.

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class Spaces$$anonymous$$pMovement : MonoBehaviour
 {
     public float pitchPower;
     public float rollPower;
     public float yawPower;
     public float enginePower;
 
     public float brakePower; 
     public float minBrakeSpeed; 
     private bool isBraking = false; 
 
     public Rigidbody rigidbody;
     private float currentSpeed;
 
     public bool throttle => Input.GetKey(KeyCode.Space);
 
     private float activeRoll, activePitch, activeYaw;
 
     private void Update()
     {
         if (throttle)
         {
             isBraking = false;
 
             transform.position += transform.forward * enginePower * Time.deltaTime;
 
             currentSpeed = Vector3.Dot(transform.forward, rigidbody.velocity);
 
             activePitch = Input.GetAxisRaw("Vertical") * pitchPower * Time.deltaTime;
             activeRoll = Input.GetAxisRaw("Horizontal") * rollPower * Time.deltaTime;
             activeYaw = Input.GetAxisRaw("Yaw") * yawPower * Time.deltaTime;
             transform.Rotate(activePitch * pitchPower * Time.deltaTime,
                     activeYaw * yawPower * Time.deltaTime,
                     -activeRoll * rollPower * Time.deltaTime, Space.Self);
 
             
 
         }
         else
         {
             currentSpeed = Vector3.Dot(transform.forward, rigidbody.velocity);
 
             
             if (currentSpeed > minBrakeSpeed)
             {
                 isBraking = true; 
             }
             else
             {
                 isBraking = false; 
             }
 
             if (isBraking)
             {
                 
                 currentSpeed -= brakePower * Time.deltaTime;
                 rigidbody.velocity = transform.forward * currentSpeed;
             }
  
         }
     }
 }

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