You guys know that I had problems with FL. I backed down and stopped the robot for a few days. Now I'm back to very slow tasks, just in case.
With that said, I've found that Stopping the tasks, then changing/updating what you need to do, clear the session cookies, and restarting; avoids most common errors "unable to retrieve...".
As for the original Instagram resetting the passwords, I don't know what the real reason was.
FL is still my choice robot for Instagram. I wish it had a few more things, or that you could have a Start/Stop time with an automated interval, so that the program would start/stop at different times every day; making it more human like. No one wakes up and starts on the app at exactly the same time every single day.
FL customer support is not the fastest, but they'll usually respond within 6 hours, as that has been my experience. Sometimes they reply back within 30 minutes, but that's not usual. And, they do not speak native English, so there are major misconceptions on what you ask and what they respond.