Dunning is the feature by which Chargebee automatically retries payment in case a payment for an invoice fails. Based on the Dunning configuration, Chargebee automatically attempts to retry the payment for the invoice after a scheduled time period. 

For a customer in dunning, you can certainly generate another invoice. Usually, a payment failure could be a one-off instance, in which case your new invoice would be paid successfully. 

In cases where the payment method is expired or the card has no funds, this new invoice would also be in Dunning and Chargebee would attempt to retry payment for this invoices. Dunning is supported for one time invoices, so if the payment fails, dunning would be initiated.

As the last dunning action, you can choose to set one of the actions to void the invoice or cancel the subscription. Click Here for more info.

Note: you can stop dunning anytime before the last action is carried out. Go to the  respective invoice and click "Stop Dunning"

Related articles & docs:

Dunning configuration - https://www.chargebee.com/docs/dunning-v2.html

Creating one time charges/invoices - https://www.chargebee.com/docs/charges.html