Here's the deal ... the late actor's Facebook account started posting a ton of strange things last week, like death hoaxes, news links and fake stories about Ellen DeGeneres, Bruce Willis, and Arnold Schwarzenegger -- all of which confused and alarmed fans who followed the late "Goodfellas" star.

Late this week, a rep for Ray's team told TMZ they'd finally resolved the issue by reaching out to Facebook and working with them to address the problem.

Or, so they thought. Shortly after we were told the account was secured ... another bizarre post -- for Ray's page, at least -- went up promoting a porn scene. It has since been removed.

We've reached out regarding the porn post, but no word back yet.

While his team told us they believed the account was back in good hands ... that doesn't seem to be the case.

The troubling part is it seems a mystery as to who's been hacking his page and how these posts keep ending up on his feed. All the old phony posts have been deleted, but it's clear someone is still using his account with ill intentions.

Despite the scary security breach, Ray's camp says Mark Zuckerberg's company has been "an amazing partner in resolving the issue."

As you know, Ray died in his sleep last May, when the 67-year-old was filming a movie in the Dominican Republic.