Transactions and Invoices
Each transaction is related with one of your users, a subscription. This is the actual piece of data that control whether your user is having an active, or not subscription.
After a successful purchase a transaction is automatically created and saved in the database. You can view, edit, cancel, or even manually create a transaction from back end, in tab Transactions.
To cancel a subscription just edit the corresponding transaction and press button Cancel Transaction. If you cancel a transaction, the next time user tries to login, he will be automatically moved to the non-active user groups. It's the same like his available days ended.
If for some reason you wish to create a transaction for a user (for example you received a manual bank payment), you can also do it from that tab. You can also view the invoice created for each transaction and manually send via email to your user.
The transaction id is the same as the one of the PayPal transaction id.
Each of your customers can access his invoices in front end. To activate this functionality, all you have to do is to create a front end menu, and choose SP Digital Subscriptions->Invoices. See below image as an example what your user will see:
By click on the transaction id link user can view and print the invoice.