通过Postman在Asp.net Core API中发布数据时将值转换为类型时出错

我正在Asp.net Core中开发API。我有联系人和职位模型。

Contact.cs

public class Contact
{
    [Key]
    public int ContactId { get; set; }

    //public string UserId { get; set; }

    [Required]
    [StringLength(20)]
    public string FirstName { get; set; }

    [StringLength(20)]
    public string MiddleName { get; set; }

    [Required]
    [StringLength(20)]
    public string LastName { get; set; }

    [StringLength(60)]
    public string FullName { get; set; }

    [Required]
    public Gender Gender { get; set; }

    [Required]
    public DateTime DateOfBirth { get; set; }

    public MaritalStatus MaritalStatus { get; set; }

    [Required]
    public JobTitle JobTitle { get; set; }

    [Required]
    [EmailAddress]
    [StringLength(50)]
    public string Email { get; set; }

    public int Phone { get; set; }

    [Required]
    public int Mobile { get; set; }

    public string Address { get; set; }
    public string Photo { get; set; }
    public bool IsDeleted { get; set; }
    public DateTime CreatedOn { get; set; }
    public DateTime UpdatedOn { get; set; }
}

public enum Gender
{
    Male = 0,
    Female = 1
}

public enum MaritalStatus
{
    Unmarried = 0,
    Married = 1,
    Divorced = 2,
    Widowed = 3
}

Jobtitle.cs

public class JobTitle
{
    [Key]
    public int Id { get; set; }

    [Required]
    [StringLength(50)]
    public string Name { get; set; }

    [Required]
    [StringLength(50)]
    public string NameAr { get; set; }

    public bool IsDeleted { get; set; }
    public DateTime? CreatedOn { get; set; }
    public DateTime? UpdatedOn { get; set; }
    public virtual ICollection<Contact> Contact { get; set; }
}

我正在使用邮递员发布我的JSON数据以在联系人中插入新值，但它给了我错误：

JSON值

{
"firstName": "XYZ",
"middleName": "",
"lastName": "ABS",
"fullName": "XYZ ABS",
"gender": 0,
"dateOfBirth": "1987-03-05T07:49:33",
"maritalStatus": 1,
"jobTitle": "1",
"email": "[email protected]",
"phone": 12345678,
"mobile": 12345678,
"address": "84445 abc Hill",
"photo": "",
"isDeleted": false,
"createdOn": "2018-03-07T03:41:44",
"updatedOn": "2018-03-07T03:41:44"
}

将值转换为Jobtitle对象类型时出现错误。

"errors": {
"jobTitle": [
  "Error converting value \"1\" to type 'TransConnectApi.Models.JobTitle'. Path 'jobTitle', line 9, position 17."
]
}

我知道问题在于API需要引用jobtitle对象，但是我不知道该如何解决，因为它没有达到Visual Studio中的发布断点。那么，如何才能获得Jobtitle的价值并将其转换呢？