Possible PayPal Glitch

I'm going to call it a glitch because the people who've contacted PayPal about the message are not being told anything concrete as far as I can tell.

I've paid many a PayPal invoice over the years, but suddenly this year I've gotten three that all had this at the top: "Transaction cannot be processed because the invoice has been updated, canceled, paid, or closed; contact the merchant for more information."

Looks like this...

It shows up after I try to hit PAY INVOICE at the bottom of the invoice (not shown in this photo).

I try multiple times and it just doesn't work.

On a lark, I clicked on PAY INVOICE at the top, just under the error message.  And my payment went through.  Weird, huh?

So if you get that message, you might try doing the same thing.  Maybe something in the programming of their other button is funky.