After any of your customers has processed a payment, you can send a message to that customer in order to tell them that you have received their payment.
Not only will they feel reassured, but, they will have the certainty that they did the payment without any mistakes.
As soon as a customer has paid an invoice, you will get an email notification and, the invoice card will display Paid.
In your company settings, you can set up a preset message and send it every time a payment has been processed. Here are a few payment confirmation messages examples you can use.