Need an "aMember Pro V3.1.2" Membership Software EXPERT!

We are currently using “aMember Pro Version 3.1.2,” and are experiencing an issue with the PAYPAL plugin checkout. HERE'S THE PROBLEM: 1. The member selects their “subscription,” selects “PAYPAL” as their method of payment, then clicks the “Subscribe” button to checkout. 2. They arrive on the 2nd page that says: “You will be automatically redirected to secure payment page in about 2 seconds” 3. They then arrive on the 3rd and last page which is a PayPal URL: [login to view URL] With this error message: “The link you have used to enter the PayPal system is invalid. Please review the link and try again.” FACT #1: If the member selects another payment checkout such as “CLICKBANK,” everything is working fine (i.e. they are able to checkout). FACT #2: The PayPal IPN is working fine, as we are currently receiving notifications from PayPal FACT #3: Every time the member attempts to checkout with “PAYPAL,” it registers in our aMember admin and displays the correct “Paid” and “Status” info (e.g. Paid = NO, Status = Non-Paid). Respond with "aMember Pro EXPERT" in your private message subject line, or else I won't read it. Thank you.