My site have face the same problem for many times, that is when some of my customer check-out, the process will come to a point where they are told "You will be forward to PayPal to complete your purchase", but when they click "confirm" or "next", a message from the next page will shows them saying " The purchase has been paid for ", which actually they have not even been forward to PayPal to log-in yet !!
Anyone has any idea what when wrong here ? Please kindly help me and Thank You Very Much for Your Time taken.
My site is www.catappaleaves.com