Amount configuration error You are getting an error because the amount is not configured in the Summary settings. Please follow the instructions below to update it. Summary setttings Login to Neartail. Click on the form to open it. Edit page will be displayed. In the Neartail edit page, click on the gear icon next to the form title. Form settings page will be displayed. Click on the configure fields icon next to the Save button in the bottom right corner. Summary settings page will be displayed. You must select the correct field for the Amount option and click Save. The value from the selected field will be passed as the amount to be charged to Stripe. This field must have a valid number. Otherwise, payments will not work. Calculate Transaction Fee In the Neartail Edit page, click on the Add price field icon > select Tip, click Next > Update the title "Transaction fee", select Percentage option, click Next > Enter the percentage for order amount and click Create. For example, you can charge 4% of the order amount as the transaction fee. Calculate total amount including transaction fee In the Neartail Edit page, click on the Add price field icon > select Net amount, click Next > select Standard calculation using NETTOTAL() formula, click Next > click Create. NETTOTAL function calculates the net amount based on the fields mapped in the Summary settings page. It will automatically add the fields mapped for Amount, Delivery Fee, Tip, Taxes and subtract the Discount to calculate the net amount. When you use the Add price field option, it automatically maps the fields in the Summary settings page. If you use the Add field option, you will have to manually map the fields in the Summary settings page.

What if I want to add 2.9% + 30 cents?

You can add the formula to calculate the transaction fee as required. If it is fixed amount + a percentage fee, the you can add a custom formula. (Order Amount * 0.029) + 0.30 You must type @ and select the Order Amount field from the list to list to include it in the formula when adding it in the Calculate option.

everything works now. The only issue is that the total shows 30 cents by default, which is annoying

You can use the IFS condition to check if the order amount is greater than 0 and then calculate the transaction fee. IFS(Order Amount > 0, (Order Amount * 0.029) + 0.30, 0)

Thanks, it worked