Nested resources give nil when trying to use

[iviv122]

Godot Version

Godot 4.5stable

Question

I have 3 classes for simplicity

Item

extends Resource 
class_name Item

@export var ItemName : String

Recipe

extends Resource 
class_name Recipe 

@export var item1 : Item 
@export var item2 : Item
@export var result : Item

Printer

extends Node

@export var recipe : Recipe

func _ready() -> void:
	print(recipe.item1.ItemName)
	print(recipe.item2.ItemName)
	print(recipe.result.ItemName)

And when i am trying to run it gives next error

E 0:00:00:359   _ready: Invalid access to property or key 'ItemName' on a base object of type 'Nil'.
  <GDScript Source>print.gd:6 @ _ready()
  <Stack Trace> print.gd:6 @ _ready()

In inspector everything seems to be ok and loaded. What is wrong?

[hexgrid]

item1 appears to be uninitialized. Are you setting it somewhere?

[iviv122]

So i don’t know how but switching from .tres to .res helped