Question: Will the merchant receive a confirmation email once the payment is done?

Answer: Notification emails are not sent to the merchant, instead, the merchant can configure an IPN Instant Payment Notification (IPN) Service.

As soon as a transaction is created or altered, IPN will instantly send a notification to the merchant’s specified IPN Listener URL, which can have any code that will assist in updating ERP or dependent systems. Alternatively, the merchant may wish to save this information in his local database.

Developers | Payment Notifications| Configuration

Then enter your URL http://xxx


Choose SendGrid Option

API Key: from merchant's SendGrid dashboard
From: email address 
To: email address

Up next: Setting up SendGrid