There could be multiple reasons why the payment failed.
As a new subscriber to the service, a failed payment will suspend your access to Ubisoft+. While your subscription is suspended, you will not be able to access any of the games that are provided with Ubisoft+.
To regain access to the service, please make a payment with your existing payment method or change it via the subscription management page. You will need to update your payment method within seven days to resume your subscription, otherwise your subscription will be cancelled.
Once you add a valid payment method, your subscription will resume. If the suspension occurred during an active billing period, your subscription will be extended by the number of days your service was suspended for. Your new billing date will be adjusted automatically and can be seen in your account.
As an existing subscriber you will receive a notification email about the failed payment. You then have seven days to provide a valid payment method on the subscription management page before your subscription is automatically cancelled.
Please note that your games will be accessible again once your subscription status shows as Active on the My Subscription page, or if you decide to buy them.
Have a look at our Ubisoft+ section if you have any other questions about this service.