Pay per view paypal error - 10486

Hi Team,

I am testing your pay per view plugin at the moment via Paypal live. I can confirm my API, and call back token all updated, and call back URL also updated in paypal web site. The problem i have is, I can actually press button to make payment from my site which redirect to paypal.com, and make payment, and then redirect back to my site.

However, after payment made, and when i click button: "confirm 1AUD to see the content" , i am getting error msg straight away:

There was a problem finalizing your purchase with PayPal. Please try again.

10486 – This transaction couldn’t be completed. – This transaction couldn’t be completed. Please redirect your customer to PayPal.

I can confirm my testing credit card is ok, and paypal account is ok. The transaction not showing on paypal, nor on your transcation tab as well.

would you able to give me some help about checking this problem? I have spent whole night to check this out.

thank you so much.

Andy