1. Now, when there is a new sales, you will be first notified by your WooCommerce through emails. Here are the example of the notification from your mobile phone.
2. You will be also notified from senangPay, since you are subscribing senangPay
3. If you do not want to received double notification on a single sales, simply make sure that you are using different email for senangPay and your WooCommerce email setting.