System.Web.Services.Protocols.SoapException: Server was unable to process request. ---> System.Data.OleDb.OleDbException: Syntax error in INSERT INTO statement.
   at System.Data.OleDb.OleDbCommand.ExecuteCommandTextErrorHandling(OleDbHResult hr)
   at System.Data.OleDb.OleDbCommand.ExecuteCommandTextForSingleResult(tagDBPARAMS dbParams, Object& executeResult)
   at System.Data.OleDb.OleDbCommand.ExecuteCommandText(Object& executeResult)
   at System.Data.OleDb.OleDbCommand.ExecuteCommand(CommandBehavior behavior, Object& executeResult)
   at System.Data.OleDb.OleDbCommand.ExecuteReaderInternal(CommandBehavior behavior, String method)
   at System.Data.OleDb.OleDbCommand.ExecuteNonQuery()
   at Service.Insertm(Users user)
   --- End of inner exception stack trace ---

 protected void Button1_Click(object sender, EventArgs e)
    {
        localhost.Users newuser = new localhost.Users();
        localhost.Service ms = new localhost.Service();
        newuser.ID = ms.GetLastUserID();
        newuser.Name=nametxt.Text;
        newuser.Password=passwordtxt.Text;
        newuser.Email = emailtxt.Text;
        newuser.Avatar = avtartxt.Text;
        newuser.Phone = phonetxt.Text;
        newuser.Group = 1;
        newuser.City = citytxt.Text;
        ms.Insertm(newuser);
        ActionLabel.Text = "נרשמת בהצלחה";
    }

using System;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
using System.Data;
using System.Data.OleDb;


public class Service : System.Web.Services.WebService
{
    public Service () {
        //Uncomment the following line if using designed components 
        //InitializeComponent(); 
    }
    
    public DataSet Insertm(Users user)
    {
        string st;
        DataSet ds = new DataSet();
        int x;
        st = @"provider=Microsoft.jet.oledb.4.0;Data Source = " +
            Server.MapPath("~/Data/db6.mdb");
        OleDbConnection conn = new OleDbConnection();
        conn.ConnectionString = st;
     
        OleDbCommand cmmd = new OleDbCommand("INSERT INTO Users (user_id,user_name,password,email,user_group,city,phone,avatar) VALUES(@idparam,@nameparam,@passwordparam,@emailparam,@groupparam,@cityparam,@picparam)", conn);
        cmmd.Parameters.Add("@idparam", OleDbType.Numeric).Value = (int)user.ID;
        cmmd.Parameters.Add("@nameparam", OleDbType.VarChar).Value = user.Name.ToString();
        cmmd.Parameters.Add("@emailparam", OleDbType.VarChar).Value = user.Email.ToString();
        cmmd.Parameters.Add("@passwordparam", OleDbType.VarChar).Value = user.Password.ToString();
        cmmd.Parameters.Add("@groupparam", OleDbType.Numeric).Value = (int)user.Group;
        cmmd.Parameters.Add("@cityparam", OleDbType.VarChar).Value = user.City.ToString();
        cmmd.Parameters.Add("@picparam", OleDbType.VarChar).Value = user.Avatar.ToString();
        conn.Open();
        x = cmmd.ExecuteNonQuery();
        if (x != 0)
        {
            string my_quary2 = "Select * Users";
            OleDbCommand cmmd2 = new OleDbCommand(my_quary2, conn);
            OleDbDataAdapter da = new OleDbDataAdapter(cmmd2);
            da.Fill(ds);
        }
        conn.Close();
        return (ds);
        //return cmmd.CommandText.ToString();
    }
    
    public int GetLastUserID()
    {
        DataSet ds = new DataSet();
        string st = @"provider=Microsoft.jet.oledb.4.0;Data Source = " +
          Server.MapPath("~/Data/db6.mdb");
        OleDbConnection conn = new OleDbConnection();
        conn.ConnectionString = st;
        conn.Open();
        string my_quary2 = "Select * From Users";
        OleDbCommand cmmd2 = new OleDbCommand(my_quary2, conn);
        OleDbDataAdapter da = new OleDbDataAdapter(cmmd2);
        da.Fill(ds);
        conn.Close();
        if (ds.Tables.Rows.Count != 0)
        {
            return int.Parse(ds.Tables.Rows.Rows.Count - 1].ToString()) + 1;
        }
        else
        {
            return 0;
        }
        
    }
}