A lot of merchants including us are having the same issue. As usual paypal's support sucks. I notified them about this a few weeks ago when it first happened to us, and the "support" guy said something like:

"Sometimes things like this happen on websites"

I suggested he report it to the dev team, but I guess that didn't happen. It's hard to know if paypal even knows about it, as they don't seem to have a site status page. (There is paypal-notify.com, but you need to log in to even see the status, and I can't be bothered investigating to see if it is actually a legitimate paypal site rather than a scam site).

WTF paypal!

I was just looking at alternatives. It seems stripe is about the only alternative that supports subscriptions, but a lot of people are saying their support sucks balls as well.