Recurring payment towards your subscription fails when the last auto-charge is unsuccessful and all three retries have been exhausted. This can happen due to an error from the bank, the wallet gateway, or insufficient funds. 

While this would not affect your production environment, an invoice would be generated as per your subscription cycle, which needs to be paid manually every time. Your subscription status will stay in a halted state. You can read more about the Types of Subscription statuses.

However, you can move your subscription status back to an Active state by updating your payment method. The new method will be active from the next billing cycle. 

And that's all! Hope it helped!