Having a problem trying to save data

Hey guys,

I'm having an issue trying to implement save/load functionality into my game.

I have a test scene in which a cube can move around with the WASD keys. F5 saves the cube's location as well as a few other variables to a .json file, and F9 loads that saved data. So if you hit F9 to load, the cube will go back to the position it was at when you last hit F5 to save. And it works.

The problem I'm having is this: when I try to replicate the process, the data doesn't get saved. I just get a .json file with nothing in it. First I tried it in another project. Didn't work. I went back to my test project, and created a new scene. I took all of the game objects, which are all prefabs, and put them in the new scene. To the best of my knowledge, both scenes and everything in them, are identical. And it still doesn't work in the second scene.

I have an empty game object called GameGlobals that has the following script attached:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class GameGlobals : MonoBehaviour
 {
     public static GameObject Player;
     public static Player ref_Player;
 
     public static SaveData ref_SaveData;
     public static SaveLoad ref_SaveLoad;
 }

I have a cube called Player that has the following script attached:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class Player : MonoBehaviour
 {
     public string playerName = "Rigel One";
     public Vector3 playerLocation;
     public float playerHealth = 100;
     public int playerAmmo = 40;
 
     public float moveSpeed;
 
     void Awake()
     {
         GameGlobals.Player = this.gameObject;
         GameGlobals.ref_Player = this;   
     }
 
     void Update ()
     {
         transform.Translate(moveSpeed * Input.GetAxis("Horizontal") * Time.deltaTime, 0f, moveSpeed * Input.GetAxis("Vertical") * Time.deltaTime);
 
         playerLocation = transform.position;
 
         GameGlobals.ref_SaveLoad.UpdateSaveData();
     }
 }

I have an empty game object called SaveManager that has the following script attached:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using System.IO;
 
 public class SaveLoad : MonoBehaviour
 {
     private string FilePath;
      public SaveData saveData;

     void Awake()
     {
         GameGlobals.ref_SaveLoad = this;  
     }
 
     void Start ()
     {
         FilePath = Path.Combine(Application.persistentDataPath, "save.txt");
     }
     
     void Update ()
     {
         // If F5 is pressed, run the Save function
         if (Input.GetKeyDown(KeyCode.F5))
         {
             Save();
             Debug.Log("save function executed");
         }
 
         // If F9 is pressed, run the Load function
         if (Input.GetKeyDown(KeyCode.F9))
         {
             Load();
             Debug.Log("load function executed");
         }
     }
 
     public void Save()
     {
         // Debug code - see if the file exists
         if (File.Exists(FilePath))
         {
             // If it does, delete it
             File.Delete(FilePath);
         }
 
         string jsonString = JsonUtility.ToJson(saveData);
         File.WriteAllText(FilePath, jsonString);
 
         Debug.Log("Player saved to " + FilePath);
     }
 
     public void Load()
     {
         string jsonString = File.ReadAllText(FilePath);
         JsonUtility.FromJsonOverwrite(jsonString, saveData);
 
         UpdateLoadData();
     }
 
     public void UpdateSaveData()
     {
         GameGlobals.ref_SaveData.save_PlayerName = GameGlobals.ref_Player.playerName;
         GameGlobals.ref_SaveData.save_PlayerLocation = GameGlobals.ref_Player.playerLocation;
         GameGlobals.ref_SaveData.save_PlayerHealth = GameGlobals.ref_Player.playerHealth;
         GameGlobals.ref_SaveData.save_PlayerAmmo = GameGlobals.ref_Player.playerAmmo;
     }
 
     public void UpdateLoadData()
     {
         GameGlobals.ref_Player.playerName = GameGlobals.ref_SaveData.save_PlayerName;
         GameGlobals.ref_Player.playerLocation = GameGlobals.ref_SaveData.save_PlayerLocation;
         GameGlobals.ref_Player.transform.position = GameGlobals.ref_SaveData.save_PlayerLocation;
         GameGlobals.ref_Player.playerHealth = GameGlobals.ref_SaveData.save_PlayerHealth;
         GameGlobals.ref_Player.playerAmmo = GameGlobals.ref_SaveData.save_PlayerAmmo;
     }
 }

I have an empty game object called DataManager that has the following script attached:

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 [System.Serializable]
 public class SaveData : MonoBehaviour
 {
     public string save_PlayerName;
     public Vector3 save_PlayerLocation;
     public float save_PlayerHealth;
     public int save_PlayerAmmo;
 
     void Awake()
     {
         GameGlobals.ref_SaveData = this;   
     }

If anyone can see what it is that I'm doing wrong, you will be saving my sanity by letting me know.

Thanks in advance.