Required field that reports status of opt-in or login bypass
attempt. 0 = Success, successful opt-in or RefreshToken
corresponding to AccessToken specified in
SetExpressCheckout is valid (user is still opted in). 1 =
New RefreshToken was generated (user is still opted in). 2
= Invalid ID, RefreshToken corresponding to AccessToken
specified in SetExpressCheckout is invalid (user is opted
out). -2 = Internal Error, system error or outage during
opt-in or login bypass. Can retry opt-in or login bypass
next time. Flow will force full authentication and allow
buyer to complete transaction. -1 = None, the field does not
represent any valid value of the status.