I'm not getting an error message, it is just bringing me to the paypal homepage instead of the page to actually purchase the shirt.
Thanks for pointing out the problem. It's resolved now. The content management system I'm using for the main website is very finicky about HTML code being embedded in the pages. It had kindly cleaned up my HTML by removing important Paypal referral information.
Also, Mrs. Peach, you
were the first person to become a Friend of the Flat Earth Society. I urge you to not act hastily and get a tattoo to commemorate the occasion. Not until you've had a day or two to think it over, at least. And, yes, I also got your request in the Paypal transaction. So that part is definitely working too, which is nice.