Resolve an issue for Microsoft.EntityFrameworkCore.DbUpdateConcurrencyException

I have an issue during an insert operation into the table using Entity Framework Core.

_context.Entry(item).State = EntityState.Added;
var r = await _context.ServiceWorkOrders.AddAsync(item);
_context.SaveChangesAsync(); <-- (fails)

Some context when dealing with this issue.

• The table is owned by client so I have to work around this issue
• The table to insert into, contains triggers and stored procedures set to run after Insert/Update/Delete operations.
• The table have relationship properties (Foreign keys)
• The table's primary key is set to auto-increment, hence the primary key field of the inserting entity is set to 0, along with the fields that is required during this insert.

I am trying to use Stored Procedure directly using ExecuteSqlCommand, but I would prefer to use EF to manage the database access. Moreover, correct me if I am wrong, I would have to list all the optional parameters in the Stored Procedure in order to add the entity in to prevent writing into the wrong fields. Currently this method inserts the entity, but it writes on the wrong fields, even if I used SqlParameters("@named_field", value).

I have tried using the Synchronous method as well, but it gives the same exception.

The exception returned:

Microsoft.EntityFrameworkCore.DbUpdateConcurrencyException: 'Database operation expected to affect 1 row(s) but actually affected 0 row(s). Data may have been modified or deleted since entities were loaded. See http://go.microsoft.com/fwlink/?LinkId=527962 for information on understanding and handling optimistic concurrency exceptions.'

edit:

Here is the entity model:

[Table("ASM_ServiceWorkOrder")]
public class ServiceWorkOrder: BaseEntity
{

    [Key, Column(name: "ROWUID"), DatabaseGenerated(DatabaseGeneratedOption.Identity)]
    public int RowUID { get; set; }

    [Column(TypeName = "nvarchar(25)")]
    public string CompanyID { get; set; }

    [DatabaseGenerated(DatabaseGeneratedOption.Computed)]
    public string DocNumber { get; set; }

    [DatabaseGenerated(DatabaseGeneratedOption.Computed)]
    public string RevisionNumber { get; set; }

    [Column(TypeName = "nvarchar(40)")]
    public string CustomerDirectoryID { get; set; }

    [ForeignKey("CustomerLocation")]
    public Int32? CustomerLocationRowUID { get; set; }

    public AssetLocation CustomerLocation { get; set; }

    [Column(TypeName = "nvarchar(50)")]
    public string WorkOrderType { get; set; }

    [Column(TypeName = "nvarchar(25)")]
    public string IssueType { get; set; }

    [Column(TypeName = "nvarchar(40)")]
    public string AssetItemCode { get; set; }

    [Column(TypeName = "nvarchar(40)")]
    public string AssetSerialNo { get; set; }

    [ForeignKey("AssetRegister")]
    public int? AssetRegisterROWUID { get; set; }

    public AssetRegister AssetRegister { get; set; }

    [Column(TypeName = "nvarchar(40)")]
    public string ProjectDirectoryID { get; set; }

    [Column(TypeName = "nvarchar(10)")]
    public string Priority { get; set; }

    [Column(TypeName = "nvarchar(25)")]
    public string Status { get; set; }

    [Column(TypeName = "nvarchar(25)")]
    public string StatusForClient { get; set; }


    public bool? Billable { get; set; }

    [Column(TypeName = "decimal(18, 2)")]
    public decimal? QuotedFee { get; set; }


    [Column(TypeName = "datetime")]
    public DateTime? DueDate { get; set; }

    [Column(TypeName = "nvarchar(240)")]
    public string Description { get; set; }

    [Column(TypeName = "nvarchar(50)")]
    public string ReportedBy { get; set; }


    [Column(TypeName = "datetime")]
    public DateTime? ReportedDate { get; set; }

    [Column(TypeName = "nvarchar(35)")]
    public string BusinessDataType { get; set; }

    [Column(TypeName = "nvarchar(240)")]
    public string DocRemarks { get; set; }

    [Column(TypeName = "nvarchar(2000)")]
    public string ErrorText { get; set; }


    public Guid? RowGlobalUID { get; set; }


    public Int32? HeaderROWUID { get; set; }


    [Column(TypeName = "datetime"), DatabaseGenerated(DatabaseGeneratedOption.Computed)]
    public DateTime? DateOfDocument { get; set; }

    //[Timestamp]
    //public byte RowVersion { get; set; }

    //public IList<ServiceWorkOrderAttachment> Attachments { get; set; }

    public IList<ServiceWorkOrderDetails> Details { get; set; }


}