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Entity Framework suggest invalid field name

I have two tables in my DataBase, BUNTS , which contains information about pieces of steel

CREATE TABLE BUNTS (
    BUNTCODE         INTEGER NOT NULL,
    BUNTNAME         VARCHAR(20),
    BUNTSTEEL        INTEGER,
    ......
);

and POLL_WEIGHT_BUNTS , which contains information about operations that had been performed on each bunt

CREATE TABLE POLL_WEIGHT_BUNTS (
    PWBCODE            INTEGER NOT NULL,
    PWBBUNTCODE        INTEGER,
    PWBDEPARTMENTFROM  INTEGER,
    PWBDEPARTMENTTO    INTEGER
    ....
);

The relationship is one-to-many. I mapped those tables to models. Everything worked just fine. Recently I've decided to add a field to table BUNTS which would reference to the last operation that had been performed on bunt:

BUNTLASTOPER     INTEGER

Now my models look like this:

[Table("BUNTS")]
public class Bunt
{
    [Key]
    [Column("BUNTCODE")]
    public int? Code { set; get; }
    [Column("BUNTNAME")]
    public string Name { set; get; }
    [Column("BUNTSTEEL")]
    public int? SteelCode { set; get; }
    [Column("BUNTLASTOPER")]
    public int? LastOperationID { set; get; }
    [ForeignKey("LastOperationID")]
    public BuntOperation LastOperation { set; get; }
    public virtual ICollection<BuntOperation> Operations { set; get; }
}

[Table("POLL_WEIGHT_BUNTS")]
public class BuntOperation
{
    [Key]
    [Column("PWBCODE")]
    public int? Code { set; get; }
    [Column("PWBBUNTCODE")]
    public int? BuntCode { set; get; }
    [ForeignKey("BuntCode")]
    public Bunt Bunt { set; get; }
    [Column("PWBDEPARTMENTFROM")]
    public int? DepartmentFromCode { set; get; }
    .....
}

After I've made this, when I try to query Operations like this

return _context.Operations;

it generates an SQL-statement with new incorrect field Bunt_Code

SELECT 
"B"."PWBCODE" AS "PWBCODE", 
"B"."PWBBUNTCODE" AS "PWBBUNTCODE", 
"B"."PWBDEPARTMENTFROM" AS "PWBDEPARTMENTFROM", 
....
"B"."Bunt_Code" AS "Bunt_Code"
FROM   "POLL_WEIGHT_BUNTS" AS "B"

I assume that now EF looks for a field that is a foreign key for BUNTS table, and cant find it. So it generates Bunt_Code field, which is missing in my database. But I already have a property Bunt in BuntOperation class, which references to BUNTS table. What am I missing?


UPDATE seems like this solves my problem

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    modelBuilder.Entity<Bunt>().HasOptional(b => b.LastOperation).WithMany();
    modelBuilder.Entity<Bunt>().HasMany(b => b.Operations).WithRequired(op => op.Bunt);
}

seems like this solves my problem

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
     modelBuilder.Entity<Bunt>().HasOptional(b => b.LastOperation).WithMany();
     modelBuilder.Entity<Bunt>().HasMany(b => b.Operations).WithRequired(op => op.Bunt);
}

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