.Net Core2 EF MySQL having issue while changing foreign key column to nullable (no replies)

I am working on an application where I am using .Net Core 2, EF Core and MySQL as database server via Code First approach.

I have 2 tables:

User
Employee

User table is the main table which contains the user information and Employee table is the child table which has a column ID_User as shown below:

public class User : BaseEntity
{
public int ID_User { get; set; }
public string Name { get; set; }
public string UserName { get; set; }
public string Password { get; set; }

public virtual ICollection<Employee> Employees{get;set;}
}



public class Employee : Entity
{
public int ID_Employee { get; set; }
public string Name { get; set; }

public int ID_User { get; set; }

public virtual User User { get; set; }
}

Everythihg works perfectly when I use the above mapping and I have enaugh data in both the tables.

Now, I want to make the column ID_User in Employee table as nullable

To implement this change I made folloeing change to my model:

public class Employee : Entity
{
public int ID_Employee { get; set; }
public string Name { get; set; }

public int? ID_User { get; set; }

public virtual User User { get; set; }
}

and in mapping file:

builder.HasOne(x=>x.User).WithMany(y=>y.Employees).HasForeignKey(z=>z.ID_User).IsRequired(false);

After running the dotnet ef migrations add empuser command it generated the following migration code:

migrationBuilder.DropForeignKey(
name: "FK_Employee_User_ID_User",
table: "Employee");

migrationBuilder.AlterColumn<int>(
name: "ID_User",
table: "Employee",
nullable: true,
oldClrType: typeof(int));

migrationBuilder.AddForeignKey(
name: "FK_Employee_User_ID_User",
table: "Employee",
column: "ID_User",
principalTable: "User",
principalColumn: "ID_User",
onDelete: ReferentialAction.Restrict);

Now when I run dotnet ef database update it is giving me the following error:

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'CONSTRAINT FK_Employee_User_ID_User' at line 1

Please help.

Thanks