Let me help you resubscribe so that you can get back on track.
You'll be prompted to resubscribe as soon as you login to your QuickBooks Online account. If you're not prompted, here's how you can do it inside QuickBooks:
Here's how:
Go to your Gear icon and choose Account and Settings.
Select Billing & Subscription and click the Resubscribe link.
Enter the new billing information. Then, select Subscribe.