PayPal Adaptive Payments: ExecutePayment returns payKey AP-XXXX has already been used to make a payment -

i first call pay api actiontype=create , after user has been redirected returnurl i'm calling executepayment api pay_key received @ first pay call.

pp returns error message: paykey ap-xxxx has been used make payment

does know trigger error , how solve it?

thanks

you doing explicit payment (redirecting user papal website) , therefore confirmation of user leads execution of payment. take here: https://stackoverflow.com/a/29473433/1536921