Hi Zetha1982, Thank you for your post. It seems that your purchase token is invalid. Though it's sending 500. How did you obtain this token and user id? Also, please do not post the url with your dev secret in the forum which is publicly visible. If you want you can come through ContactUs. Please mention about this thread url (
https://forums.developer.amazon.com/forums/thread.jspa?threadID=1075&tstart=0) in ContactUs.