Self-referencing relationship in EF Core 5 - entity-framework-core

Question

I'm trying to create a tree structure in the db where items can reference each other. I was considering that to be a simple task, however, EF Core decided to strike. I can't get it to generate the correct foreign keys, it keeps throwing an exception:
Unable to determine the relationship represented by navigation 'Item.Parent' of type 'Item'. Either manually configure the relationship, or ignore this property using the '[NotMapped]' attribute or by using 'EntityTypeBuilder.Ignore' in 'OnModelCreating'.
My class looks like this (simplified):
public class Item
{
[Key]
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public Guid Id { get; set; }
[ForeignKey("Parent")]
public Guid? ParentId { get; set; }
public virtual Item Parent { get; set; }
[InverseProperty("Parent")]
public virtual IEnumerable<Item> Children { get; set; }
}
I have even tried to remove the Children property, but with the same result.
Another thing I have tried was Fluent API:
entity
.HasOne(e => e.Parent)
.WithMany(e => e.Children)
.HasForeignKey(e => e.ParentId);
//or
entity
.HasOne<Item>(e => e.Parent)
.WithMany()
.HasForeignKey(e => e.ParentId);
//or
entity
.HasMany(e => e.Children)
.WithOne(e => e.Parent)
.HasForeignKey(e => e.ParentId);
//or
entity
.HasMany(e => e.Children)
.WithOne(e => e.Parent);
They all keep generating the same error, I'm kind of lost on what am I doing wrong.
I was looking at some other answers too and they look pretty much like what I'm trying to do, however, my EF will not generate the migration.

Answer 1

Disregard this question, I've figured out my own mistake. I will leave it here in case someone faces the same problem as the error message is very misleading.
What has happened was a copy&paste issue where I have created another configuration for an unrelated entity, but forgot to update the type:
{
public void Configure(EntityTypeBuilder<Item> entity)
{
entity
.HasNoKey();
}
}
Notice the Item type in the generics definition. This lead the EF Core to wipe out the key that was originally set on the entity and made EF Core confused about the relationship (as now I'm targeting foreign key to a property that's neither key nor index).