Suddenly - "The content has ended. You may close this window"

Hi everyone,

I'm having some problems with courses published in SL3. Out of nowhere I'm getting a "Close the window" message when leaving a course. I'll try to explain:

The course is published for and imported to an LMS where it is just one of many courses within that same training program (like one lesson out of several in the same program). It runs fine and looks fine, but when I try to navigate away from it by clicking on any other lesson/content within that program something happens. Instead of re-navigating to the other content like it used to, I get this message: "The content has ended. You may close this window".

Tried to search for similar topics but everything I found was connected to launching the goodbye.html due to clicking on the Finish button. I have no such button in my courses. Instead, this message is triggered by someone simply navigating away from one SL3 lesson to another within the same program in the LMS.

None of our courses has ever acted like this before, but every one of the recently updated courses now do. Does anyone have a clue why this happens? What can I do to fix it? PLEASE say there's something I can do :)

Thank you,

Towa