If you're still in the process of creating a new account, you can use the link to subscribe to QuickBooks Online: https://quickbooks.intuit.com/in/. Select to buy or start with a free trial and then enter your information that will be used as your login credentials.
If you're referring to reactivating your account, you can use these steps:
Go to the Gear icon at the upper right.
Select Account and Settings under Your Company.
Go to the Billing & Subscription menu.
Select Resubscribe.
Enter the updated billing information.
Click Subscribe.
To help you get started and learn more about our features, here are great articles you can visit:
If you have to open a new QBO account, make sure to click the Buy button to get the discounted price for up to 3 months. If you purchase from the Trial account, you have to pay the regular rate.