It turns out their was some change in the accepted email address. Now either the primary email address or the merchant ID is accepted. Before it could be either the Merchant ID or any verified address associated with the PayPal account. The documenation says: Your PayPal ID or an email address associated with your PayPal account. Email addresses must be confirmed. This should be updated to the following: Your PayPal ID or the primary email address associated with your PayPal account. Email addresses must be confirmed.
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