Open the secure subscription form located in your spreadsheet menu at Add-ons > Flookup > Manage subscription > Start subscription and follow the steps below.
Please note that some of these steps might not be available for all regions.
1. Choose your preferred subscription plan, enter your Subscriber Email Address and click "Proceed":
2. Click "Pay with Debit or Credit card":
3. Enter your email address and click "Continue to Payment":
4. Enter your credit or debit card details:
5. Click "No, I don't want an account now" and then click "Agree and Subscribe":
6. Return to your spreadsheet and click "Update status":