Scriptable objects has empty inspectors and do not exist in build

I am having problems with scriptable objects in my game. I made a single completely unrelated change at one point and all of the scriptable objects became corrupt. When clicking on the scriptable objects the inspector was completely blank, no fields were listed at all. I ended up deleting the object and recreating it. This happened multiple times before that incident, but I did not realize what happened. This does not always happen when I make changes. I don't know what causes it.

The scriptable objects are also completely absent when I build the game. I added a line of code that checks if the reference to the scriptable object is null or not and it always returns a null reference in the built version. In the editor however, everything works fine. I'm thinking unity is not including my scriptable objects in the built version.

The scriptable objects are items. I followed the inventory system tutorial on unity learn. I copied the inventory and item.cs from the tutorial. I did add some extra variables to the item.cs.

I'm almost certain there is nothing wrong with my code because I run "if (item == null)" on start() of each script that has a reference to an item. This always returns true in the built version, aside from the corruption i mentioned above it works when i run it in the editor. I take advantage of a journal type system in my game to act as a debug log.

Is there something I need to do to handle scriptable objects properly? I need to submit a built version of my game for grading. I currently cannot build a version that includes the scriptable objects.

I don't think there is an issue in my code, but I'll include some of it anyway.

item.cs

 using UnityEngine;
 using System;
 using System.Collections;
 using System.Collections.Generic;
 
 [CreateAssetMenu]
 [Serializable]
 public class Item : ScriptableObject
 {
     public string itemName = "unnamed";
     public Sprite sprite;
     public Mesh mesh;
     public Material mat;
     public string ExamineInfo;
 
 }
 

Inventory.cs (part)

     public bool AddItem(Item itemToAdd)
         {
             if (itemToAdd == null)
             {
                 journal.addLog("itemToAdd was null");
             }
    //...
     }

Pickupinteract.cs (part)

     public class PickupInteract : Interact
     {
         public Item item;
         void Start()
         {
             if (item != null)
             {
                 journal.addLog(this.name + " has item of " + item.name);
             }
             else
             {
                 journal.addLog(this.name + " has a null reference to an item");
             }
         }
     //...
     }

(PickupInteract is the script that is called when an item is to be added to the inventory. It should have a reference to the item that will be added to the inventory.)

Just to clarify, the references to the items are set by dragging the item from the project window to the item field in the script. The items are created by clicking create > item in the project window. Any help is appreciated.