It's important that your locale is set correctly in your User Settings. For most users, this should have been done during setup following the initial install of the Payable add-on. However, sometimes it gets skipped, missed, or may need to be changed later on.
The combination of your:
Country
Language
Currency
is used to determine how to detect the currency and prices in your form.
If you are seeing "Free Order" at checkout, it is good to ensure these settings match the amounts as format in your form amounts.
Step 1 - Refresh the Google Form in Edit Mode
Refresh the page and wait 5-10 seconds, this helps ensure any changes you made during setup are reflected.
Step 2 - Open the User Settings window
Select the puzzle piece icon, then Payable Forms > User Settings
Open the Payable Add-Ons menu
Click on User Settings
In the User Settings window you may set your language, country, and currency.
Step 3 - Verify the Money Formatting
Click the "Looks Good!" button in the User Settings window, and we will then show you a sample of how to format your money options in your form.
Step 4 - Refresh and Update
Refresh the form again, then update your money format in answers to match your new settings. In the Payable sidebar we show the format we're looking for as an example under the Add Sample Payments Section.
Match the format shown to your Payable amounts
NB: These User Settings are associated with your account and are applied to any forms you set up. If you change these settings, you may need to update the format of you money amounts in other active Payable Forms you are using.