I am using TEST Sandbox Credentials
Thanks for your reply. In my outline I indicated I was using Sandbox Credentials (see below cut and paste for that excerpt in my original post):
"Testing: Sandbox, Seller API credentials. Buyer Agreement executed. Using SANDBOX settings not Live API settings. (My PayPal account is active, approved and in good standing for PayPal Payments Pro Merchant Account)"
I will look in the confirm page and see if those two lines of code are there.