Вызывается исключение при выполнении запроса(я новичок)

   private void button1_Click(object sender, EventArgs e)
        {
            OleDbConnection dbConnection = new OleDbConnection(Program.ConnectionString);
            dbConnection.Open();
           Program.Money ++;
            string QueryMoney = "UPDATE Users SET Money = "+Program.Money+" WHERE Login ='"+Program.Login+"'";
            OleDbCommand dbCommand = new OleDbCommand(QueryMoney, dbConnection);
            dbCommand.ExecuteNonQuery();
}

OleDbConnection dbConnection = new OleDbConnection(Program.ConnectionString);
            dbConnection.Open();
           Program.Money ++;
            string QueryMoney = "UPDATE Users SET Money = @param1 WHERE Login = @param2";
            OleDbCommand dbCommand = new OleDbCommand(QueryMoney, dbConnection);
            dbCommand.Parameters.Add("@param1", OleDbType.Integer).Value = Program.Money ;
            dbCommand.Parameters.Add("@param2", OleDbType.VarChar).Value = Program.Login;
            dbCommand.ExecuteNonQuery();

string QueryMoney = "UPDATE Users SET Money = ? WHERE Login = ?";

   OleDbConnection dbConnection = new OleDbConnection(Program.ConnectionString);
            dbConnection.Open();
           Program.Money ++;
            string QueryMoney = "UPDATE [Users] SET [Money] = ? WHERE [Login] = ?";
            OleDbCommand dbCommand = new OleDbCommand(QueryMoney, dbConnection);
            dbCommand.Parameters.Add("@param1", OleDbType.Integer).Value = Program.Money ;
            dbCommand.Parameters.Add("@param2", OleDbType.Char).Value = Program.Login;
            dbCommand.ExecuteNonQuery();