Display (Show) message if user does NOT exist in Database using C# and VB.Net in ASP.Net

hello,

I have a problem with update user info, when i try update user info and if i add in his name like kankon, i change name to kankons then i press update its add me

Do i need add something else?

i want add a message u must register first or there is no name for kankons in data please contact Admin

SQL

USE [cm]
GO
/****** Object:  StoredProcedure [dbo].[update_User_C3]    Script Date: 22/11/2022 10:07:28 م ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
alter PROCEDURE [dbo].[update_UserS]
(
    
     @name NVARCHAR(MAX)=NULL,
	 @fileid NVARCHAR(MAX)=NULL,
	 @civilid NVARCHAR(MAX)=NULL,
	 @Countries NVARCHAR(MAX)=NULL,
	 @States NVARCHAR(MAX)=NULL,
	 @Cities NVARCHAR(MAX)=NULL,
   @mobile NVARCHAR(MAX)=NULL,
    @jop NVARCHAR(MAX)=NULL

	)
	AS
       BEGIN
      SET NOCOUNT ON;
      IF EXISTS(SELECT id FROM Table_infoname WHERE name = @name)
      BEGIN
            SELECT -1 -- name exists.
      END
	  ELSE IF EXISTS(SELECT id FROM Table_infoname WHERE civilid = @civilid)
      BEGIN
            SELECT -2 -- civilid exists.
     END
	  ELSE IF EXISTS(SELECT id FROM Table_infoname WHERE fileid = @fileid)
      BEGIN
            SELECT -3 -- fileid exists.
     END
      ELSE
      BEGIN
	  UPDATE Table_infoname 
	 SET
     
      name=@name,
	  fileid=@fileid,
      civilid=@civilid,

	   Countries=@Countries,
	    States=@States,
		 Cities=@Cities,
		 jop=@jop,
		 mobile=@mobile
		 

		 where civilid=@civilid

	  end
	
	END

code behind c#

protected void Button28_Click(object sender, EventArgs e)
{
    int Id = 0;
    string constr = ConfigurationManager.ConnectionStrings["cmConnectionString"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("update_UserS"))
        {
            using (SqlDataAdapter sda = new SqlDataAdapter())
            {
                cmd.CommandType = CommandType.StoredProcedure;
 
                if (!string.IsNullOrEmpty(fName.Text.Trim()))
                {
                    cmd.Parameters.AddWithValue("@name", fName.Text.ToString());
                }
 
                if (!string.IsNullOrEmpty(ffileid.Text.Trim()))
                {
                    cmd.Parameters.AddWithValue("@fileid", ffileid.Text.ToString());
                }
 
                if (!string.IsNullOrEmpty(fcivilid.Text.Trim()))
                {
                    cmd.Parameters.AddWithValue("@civilid", fcivilid.Text.ToString());
                }
 
                if (!string.IsNullOrEmpty(mobile.Text.Trim()))
                {
                    cmd.Parameters.AddWithValue("@mobile", mobile.Text.ToString());
                }
                if (!string.IsNullOrEmpty(joptitel.Text.Trim()))
                {
                    cmd.Parameters.AddWithValue("@jop", joptitel.Text.Trim());
                }                      
 
                if (!string.IsNullOrEmpty(ddlCountries2.Text.Trim()))
                {
                    cmd.Parameters.AddWithValue("@Countries", ddlCountries2.Text.ToString());
                }
                if (!string.IsNullOrEmpty(ddlStates2.Text.Trim()))
                {
                    cmd.Parameters.AddWithValue("@States", ddlStates2.Text.ToString());
                }
                if (!string.IsNullOrEmpty(ddlCities2.Text.Trim()))
                {
                    cmd.Parameters.AddWithValue("@Cities", ddlCities2.Text.ToString());
                }
 
                cmd.Connection = con;
                con.Open();
                Id = Convert.ToInt32(cmd.ExecuteScalar());
                con.Close();
            }
            string message = string.Empty;
            switch (Id)
            {
                case -1:
                    message = "اسم المستخدم موجود مسبقا";
                    break;
 
                case -2:
                    message = "الرقم المدني مستخدم";
                    break;
                    case -3:
 
                    message = "رقم الملف مستخدم";
                    break;
 
                default:
                    message = "تم تحديث بيانات الموظف بنجاح\\nاسم الموظف : " + fName.Text.ToString();
                    
                    break;
            }
 
            ClientScript.RegisterStartupScript(GetType(), "alert", "alert('" + message + "');", true);
        }
    }
}