Input axis' switching unintentionally.

I am setting up a control script for a ship. I have everything working how i want but have one issue. So i have 3 axis' yaw, pitch and roll. The roll always stays the same as intended. The issue is with the pitch and yaw. When i turn the ship 90 degrees up or down(pitch), the yaw and pitch inputs switch.

I have the troubled axis' mapped to the right stick on an xbox one controller. So for example: Right stick up and down controls pitch and right/left controls yaw. If i pitch the ship up 90 degrees those inputs switch. UP/Down becomes yaw and Left/right becomes pitch.

Can anyone give me me an explanation why this is happening and a possible fix. Thanks very much in advance. Here is the script.

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class Movement : MonoBehaviour 
 {
     public float Speed = 200.0f;
 
     public float RollSpeed = 200.0f;
 
     public float PitchSpeed = 200.0f;
 
     public float YawSpeed = 200.0f;
 
     public float smooth = 3.5f;
 
     public Rigidbody rb;
 
     float roll = 0;
     float pitch = 0;
     float yaw = 0;
     float vertical = 0;
     float horizontal = 0;
     float thrust = 0;   
 
     void Start () 
     {
         rb = GetComponent<Rigidbody>();
     }
     
 
     void FixedUpdate () 
     {
         Move();
     }
 
     public void Move()
     {
         Quaternion AddRot = Quaternion.identity;
 
         roll += Input.GetAxis("Roll") * (Time.deltaTime * RollSpeed);
         pitch += Input.GetAxis ("Pitch") * (Time.deltaTime * PitchSpeed);
         yaw += Input.GetAxis("Yaw") * (Time.deltaTime * YawSpeed);
         vertical = Input.GetAxis ("Vertical") * (Time.deltaTime * Speed);
         horizontal = Input.GetAxis ("Horizontal") * (Time.deltaTime * Speed);
         thrust = Input.GetAxis ("Thrust") * (Time.deltaTime * Speed);
 
         AddRot.eulerAngles = new Vector3(-pitch, yaw, -roll);
         
         AddRot = Quaternion.Euler (-pitch, yaw, -roll);
         rb.rotation = Quaternion.Slerp (rb.rotation, AddRot, Time.deltaTime * smooth);
         
         Vector3 AddPos = new Vector3(horizontal,vertical,thrust);
         AddPos = rb.rotation * AddPos;
         
         rb.AddForce(AddPos * Speed);
     }
         
 }