QuickBooks Online (QBO) subscription is always an online model. If you want to reactivate your account, you can select the Resubscribe link then enter your payment information.
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.
Once done, try to log out and log back in or refresh your browser. Then go again to the Billing & Subscription, then check the Next charge date. If the date is in the past or payment for the subscription got failed, I'd suggest contacting our Customer Support team to avoid back-billed charges.
Click Help inside QuickBooks Online.
Select Contact Us.
Enter your concern in the description field, then click Let's talk.