ช่วยดูโค้ดของหนู่หน่อยค่ะ ว่ามันผิดตรงไหนขอบคุรมากๆนะค่ะ

 void TimeCheckIn()
        {
            if (cbbActivity.Text == "")
            {
                MessageBox.Show("กรุณาใสชื่อกิจกรรมก่อน", "ข้อความระบบ");
            }
            else
            {

                conn.Open();
                SqlCommand cmd = new SqlCommand("SELECT * FROM Student WHERE StudentBarcodeID = '" + txtBarcodeID.Text + "'", conn);
                SqlDataReader dr;
                dr = cmd.ExecuteReader();
                while (dr.Read())
                {
                    if (dr["StudentBarcodeID"].ToString() == txtBarcodeID.Text)
                    {
                        string a1 = dr["StudentID"].ToString();
                        string a2 = dr["StudentName"].ToString();
                        string a3 = DateTime.Now.ToLongTimeString();
                        string a4 = DateTime.Now.ToLongDateString();
                        conn.Close();
                        SqlCommand aa = new SqlCommand("SELECT * FROM Activity", conn);
                        conn.Open();
                        SqlDataReader bb;
                        bb = aa.ExecuteReader();
                        bb.Read();
                        string b2 = bb["DateSet"].ToString();
                        string b3 = bb["TimeInSet"].ToString();
                        string b4 = bb["TimeOutSet"].ToString();
                        conn.Close();
                        
                        SqlConnection conn2 = new SqlConnection("Data Source=PIMBONPC\\SA;Initial Catalog=ProjectBarcode;Integrated Security=True");
                        SqlDataAdapter da = new SqlDataAdapter();
                        da.InsertCommand = new SqlCommand("INSERT INTO Check VALUES (@StudentID, @StudentName, @ActivityName, @DateSet, @DateIn, @TimeInSet, @TimeIn, @DateOut, @TimeOutSet, @TimeOut)", conn2);
                        da.InsertCommand.Parameters.Add("@StudentID", SqlDbType.VarChar).Value = a1;
                        da.InsertCommand.Parameters.Add("@StudentName", SqlDbType.VarChar).Value = a2;
                        da.InsertCommand.Parameters.Add("@ActivityName", SqlDbType.VarChar).Value = cbbActivity.Text;
                        da.InsertCommand.Parameters.Add("@DateSet", SqlDbType.VarChar).Value = b2;
                        da.InsertCommand.Parameters.Add("@DateIn", SqlDbType.VarChar).Value = a4;
                        da.InsertCommand.Parameters.Add("@TimeInSet", SqlDbType.VarChar).Value = b3;
                        da.InsertCommand.Parameters.Add("@TimeIn", SqlDbType.VarChar).Value = a3;
                        da.InsertCommand.Parameters.Add("@DateOut", SqlDbType.VarChar).Value = "";
                        da.InsertCommand.Parameters.Add("@TimeOutSet", SqlDbType.VarChar).Value = b4;
                        da.InsertCommand.Parameters.Add("@TimeOut", SqlDbType.VarChar).Value = "";

                        conn.Open();
                        da.InsertCommand.ExecuteNonQuery();//มันขี้น error ตรงนี้ค่ะ ว่า Incorrect syntax near the keyword 'Check'.
                        conn.Close();

                        da.SelectCommand = new SqlCommand("SELECT * FROM Check", conn);
                        ds.Clear();
                        da.Fill(ds);
                        dg.DataSource = ds.Tables[0];



                    }
                    else
                    {
                        MessageBox.Show("ไม่พบในฐานข้อมูล");
                    }
                }
            }
        }