SqlException: Invalid column name 'CountryMasterCountryId'

I am doing CRUD operation using asp .net core 6 MVC (visual studio 2022). For this i complete County Create,Update,Delete,Read operation. but now i am trying cascading dropdown in state with relation county db. when i write "public virtual CountryMaster CountryMaster" and "public virtual ICollection StateMasters" in the models on state and country it give me error of sqlException:Invalid column name 'CountryMasterCountryId'. here is CountryMaster model '''

{
    [Key]
    public int CountryId { get; set; }

    [Display(Name = "Country Name")]
    [Required(ErrorMessage ="Please Enter Country")]
    public string CountryName { get; set; } = null!;

    [Display(Name ="When Entered")]
    public DateTime WhenEntered { get; set; } = DateTime.UtcNow;

    [Display(Name ="When Modified")]
    public DateTime WhenModified { get; set; }= DateTime.UtcNow;

    public virtual ICollection<StateMaster> StateMasters { get; set; }
} '''

here is StateMasters model '''

{
    [Key]
    public int StateId { get; set; }

    [Required(ErrorMessage ="Please Enter State Name")]
    public string StateName { get; set; } = null!;

    
    [Display(Name = "Country Name")]
    public int CountryId { get; set; }

    [Display(Name = "When Entered")]
    public DateTime WhenEntered { get; set; } = DateTime.UtcNow;

    [Display(Name = "When Modified")]
    public DateTime WhenModified { get; set; } = DateTime.UtcNow;

    public virtual CountryMaster CountryMaster { get; set; } 
}

''' What i do? Is Icollection different in .net core 6 MVC?