PayPal - DoExpressCheckoutPayment - Validation iss

Question

For Every PaypPal interaction we Do: 1.SetExpressCheckoutReq 2.GetExpressCheckoutDetailsReq 3.DoExpressCheckOutPaymentReq

I do create a billing agreement first and only on scheduled/subsequent orders we use this billing agreement for reference transaction.

Our Issue is:

1. With a new PayPal account ([e-mail]) DoExpressCheckoutPaymentReq failed for CITY = SuttonsBay, with the address validation error “10736” (Shipping Address Invalid City State Postal Code) for a user (USER A). And this was corrected in the subsequent request as Suttons bay.

2. But the same PayPal account([e-mail] ) used for the second time with a different user (USER B) on the site, DoExpressCheckoutPaymentReq call succeeds for the wrong CITY = SuttonsBay and allows us to complete the order.

It is to be noted that on all scheduled order of the user, we use the DoReferenceTransactionReq, which has strict validation and this fails every time, esp. for the second scenario described above.

I would like to know why there are inconsistencies in Shipping address validation for DoExpressCheckoutPayment. It is because of this difference that our scheduled orders fails (as described in scenario 2 that allows incorrect address)

Do we any way to have strict Validation in DoExpressChecOutPayment - which solves our purpose?