Our service is integrated with the Unisender e-mail service so that you can send special messages to your customers (those who bought products through our service), or vice versa do not send any specific letters that you do not want your customers to receive.
The first thing you need to do is register an account with Unisender.
How to do it and how to set everything up correctly, watch their Knowledge base:

Most likely, you are already using this service to collect emails and mailings, so let's move directly to the integration of Unisender and Smart Payment
First you need to go to the settings tab. In the "Integration" tab we find "Unisender": https://smartpayment.pro/app/profile/edit

Activate:

Next you need to enter API key:

You can find it in your account Unisender. Go to "Account Settings" -
https://cp.unisender.com/en/v5/user/info/details?__from-spa-redirect=true

In the tab "Integration and API" we take the data we need:

We copy into the corresponding field in smartpayment.pro and save:

After that go to the section "Products":

And choose any product. After that go to the tab "Extended Settings":

Below you can see the "Unisender" mailing list:

You choose the one you need (or several at the same time).
After the customer buys this product, he will automatically be subscribed to the newsletter of your choice.
There is also a feature that allows you to remove a subscriber from the list after buying them a product.


This will give you more flexibility in working with subscribers.
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If you have any questions, please contact support service.
Sincerely, Smart Payment Team!