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How do we prevent this from happening? it's an ongoing issue. we can't have subscriptions canceled and we want people to always have auto pay on. 

How to turn off automatic cancellation if no card

Solution

The payment collection for the subscription depends on the auto-collection status set for the subscription. When activating the subscription, the system would try to collect the payment for subscription activation. When there is no valid card on file to charge the customer, the subscription was canceled with the reason - 'Subscription Cancelled No Card'. This is expected product behavior.

To avoid this, you choose to enable the dunning which attempts payment collection along with multiple reminders of your choice. 

Auto-collection option decides whether the payments for the invoices generated for the subscription are charged automatically. You can select one of the following options:

Use Customer's settings: Chargebee applies the auto-collection settings defined for the associated customer record.

Auto Collection is turned ON: Chargebee charges the customer's payment method (primary or the one assigned to the subscription) automatically when payment for the subscription is due.

Auto Collection is turned OFF: Chargebee does not automatically charge the customer's payment method when paying for the subscription is due.

- Having the auto collection status set to ON, the system would try to charge the customer when the subscription moves from Trial/Future to Active. If the system to unable to find the payment method and is not able to charge the customer, then subscriptions would be canceled automatically. If you would want the subscription to stay active, then you have to keep the auto collection status set to OFF or enable the dunning setting to retry payment collection. . 

Related articles and Documentation

https://www.chargebee.com/docs/2.0/subscriptions.html

How to enable dunning in subscriptions?