Hi there,
Thanks for your message. This is related to a known issue; I will link your case under the same bug.
Support for WooCommerce Subscriptions is integrated through PayPal vaulting, which creates a token for the payment method upon purchase.
The vaulting API however, currently does not support zero-sum checkouts to create new tokens. This means when no payment occurs, then payment methods cannot be saved. To work around this behaviour there are currently only two options:
You could either create a small sign-up fee, which will result in a first payment and the creation of a token that can be reused for later payments/renewals.
Alternatively, WooCommerce Subscriptions has a feature that can allow zero-sum checkouts without adding any payment options to the subscription; it is called “$0 Initial Checkout’. However, this feature may allow trial abuse if not combined with any other measures.
As far as I know, PayPal is working on adding support for zero-sum checkouts in the Vaulting API, but we don’t have any timeline as to when the feature could be available. We are looking at alternate ways to make this happen by potentially performing a small charge with a subsequent refund, but in our view, it’s not a reliable approach.
In any case, we want this feature to be available and will include it in the plugin as soon as we found a good way to pull it off.
Let me know if this applies to your situation and if it provides enough guidance to get to a solution.
Kind regards,
Joost