If you need a tax invoice (CFDI) for what you pay for Eva, you turn it on once and it’s generated with every charge from then on. You set it up in Settings → Subscription, in the subscription billing section.
Turn on your invoice
Choose to receive an invoice
In the subscription billing section, select Yes, generate factura.
Complete your tax details
Upload your Constancia de situación fiscal and Eva fills in your RFC, legal name, tax regime, and postal code for you. You can also enter them by hand.
Say who should receive it
Add the emails that should get the invoice (up to five).
The invoice applies from the moment you turn it on; earlier charges aren’t invoiced automatically. Turn it on before your next payment so you don’t miss it.
Find your invoices
After each payment, your most recent invoice appears in the history in that same section, along with prior months’. From there you can download the PDF and the XML (the two CFDI files).
If your tax details are incomplete, the payment still goes through, but the invoice stays pending until you fix the information. Check that your RFC and constancia are up to date.
Did a tax detail change? Update it in the same section so your next invoices come out correct. If something doesn’t add up, get in touch. 
