How do i make my Mouselook behave when changing the z rotation?

My Quaternions-based mouselook works perfectly fine when my character is upright but when the z rotation of my character is changed everything behaves weird. Here is my code:

 void Update () {
     if (axes == RotationAxes.MouseXAndY)
     {
         
         rotationX += Input.GetAxis("Mouse X") * sensitivityX;
         rotationY += Input.GetAxis("Mouse Y") * sensitivityY;

         rotationX = Mathf.Clamp(rotationX, minimumX, maximumX);
         rotationY = Mathf.Clamp(rotationY, minimumY, maximumY);
         Quaternion xQuaternion = Quaternion.AngleAxis(rotationX, Vector3.up);
         Quaternion yQuaternion = Quaternion.AngleAxis(rotationY, -Vector3.right);
         transform.rotation = xQuaternion * yQuaternion;
     }
     else if (axes == RotationAxes.MouseX)
     {
         rotationX += Input.GetAxis("Mouse X") * sensitivityX;
         rotationX = Mathf.Clamp(rotationX, minimumX, maximumX);
         Quaternion xQuaternion = Quaternion.AngleAxis(rotationX, Vector3.up);
         transform.rotation = xQuaternion;
     }
     else
     {
         rotationY += Input.GetAxis("Mouse Y") * sensitivityY;
         rotationY = Mathf.Clamp(rotationY, minimumY, maximumY);
         Quaternion yQuaternion = Quaternion.AngleAxis(-rotationY, Vector3.right);
         transform.rotation = yQuaternion;
     }
     

Thanks in advance. (yes i am a noob)