designation with same department does not exist

ALTER procedure [dbo].[spadminreg]
@UserName nvarchar(50),
@Password nvarchar(50),
@UserTypeID int,
@DepID int,
@DesigID int,
@emailaddress nvarchar(50),
@PhoneNumber nvarchar(50),
@action nvarchar(50)
 
AS
BEGIN
 
if(@action='CheckDuplicate')
  BEGIN
    Select count(*) from Userss where UserTypeID=@UserTypeID AND DepID=@DepID And DesigID=@DesigID;
  END
if(@action='Insert')
  BEGIN
   insert into [Userss](UserName,Password,UserTypeID,DepID,CreateDate,DesigID,Email ,PhoneNumber)
    values
   (@UserName,@Password,@UserTypeID,@DepID,GETDATE(),@DesigID,@emailaddress,@PhoneNumber)
   END
   end
GO

public void AdminSignUp(string Username, string Password, int UserTypeID, int DepID, int desigid, string emailaddress, string PhoneNumber)
        {
            try{
//--before using this part check proper return type for your execute scalar metod & then try to convert it to int so that you can get count of duplicate rows
      int count=  Convert.toInt32(  db.ExecuteScalar("spadminreg", new object[] { Username, Password, UserTypeID, DepID, desigid, emailaddress, PhoneNumber ,"CheckDuplicate"}));

        if(count>0)
            {
    // Duplicate entries are present
             }
          else
           {
     //Insert into data base.
         }
            }
 
 
      catch(Exception)
    {
 
     }
        }