Debug script ignoring stop();

I have a movie that has interactions in multiple frames and then passes user result data to Lectora; lastly, stops at a feedback page (a frame with stop();). It runs fine when testing movie inside Flash but it ignores the stop() and continue to run and go back to the first frame then it listens to stop() and stops at the right frame.

I read that Flash ignores stop() if there is an error. I was able to find out possible lines with problems by commenting and uncommenting multiple lines and tested multiple times. I noticed it was the script to pass data to Lectora that was causing the problem (multiple ExternalInterface.call("VarLectoraVariableName.set('"+FlashVariableName+"')")).

I double-checked all the variables making sure they exist in both Lectora and Flash, but it keep bypassing my last frame and go back to the first frame. Strangely, all the data passed to Lectora and then to LMS without any errors even when it ignores stop(). If I commented these lines, the program stops at the right frame but then no info can be passed. And the same script worked perfectly before and suddenly stopped working.

Besides scripting error, what are the other reasons Flash would ignore stop() first but then stops at the next stop()? How can I identify what it is doing when ignoring the stop()?

Thanks for any suggestions,