Payment for 3ds capture

Hi, I'm from the Uk & I'm having trouble at the checkout!
I have no idea what I'm doing
I thought I had all the details in correctly, but its not working for me.
When I hit done, I get this message
SetExpressCheckout API call failed.
Detailed Error Message: This transaction cannot be processed. The amount to be charged is zero.
Short Error Message: Invalid Data
Error Code: 10525
Error Severity Code: Error
Could anyone please help?
Thank you
I have no idea what I'm doing

When I hit done, I get this message
SetExpressCheckout API call failed.
Detailed Error Message: This transaction cannot be processed. The amount to be charged is zero.
Short Error Message: Invalid Data
Error Code: 10525
Error Severity Code: Error
Could anyone please help?
Thank you