Paystack automatically notifies businesses once payment is made. So, when a customer pays you, a receipt is immediately sent to your email confirming the payment made by the customer. The Paystack receipt typically contains the customer's name, the amount paid, transaction date etc.
For you to receive this notification when a customer pays you, kindly go to the Preferences section under Settings on your Paystack Dashboard and enable "Transaction Receipts" by ticking the box next to it. Once this is enabled, you'll be getting email notifications every time a customer pays you.
If you're using our APIs, you can also implement webhooks in order to receive automatic notifications once a transaction is successful. Your webhook URL is a link to your server where Paystack can send notifications about the status of a transaction.
If you specify a webhook URL, we'll send a response to the URL whenever an action is carried out on your website/app. This is so that if users face network issues on making a transaction, they will still receive value for their purchase since we'll still send a notification to your webhook URL.
You can see how to implement webhooks at https://developers.paystack.co/v1.0/docs/events.