If your organization uses Stripe as your payment processor, now there is a way to send recurring donors a link to update out of date credit card information.
Here are the steps:
Log in to your Stripe account
Click on BILLING, then look to the left for INVOICES
In the list, find the failed payment and click on it
When you get to the screen shown below, click on SHOW MORE
Then click INVOICE PAYMENT (shown below)
Take that URL and email it to the donor for them to use to update their credit card information
Alternatively, you can upgrade your Stripe plan to enable the full Stripe customer portal features, including one where Stripe will send automatic emails to donors at the appropriate times (such as when a payment fails, or an expiration date is coming up). Please contact Stripe for details and costs.