Insubordination?
"Flynn, it should be noted, was fired by President Obama. Fox News reports that his military career ended when Obama dismissed him as head of the Defense Intelligence Agency in 2014. Flynn has said he was pushed out for holding tougher views than Obama about Islamic extremism (this was a man who once said, “fear of Muslims is rational”). But Fox reports that a former senior U.S. official said the firing was for insubordination, after Flynn failed to follow guidance from superiors."
Not following the guidance or "free lancing" is frowned upon in the military. Unfortunately, some leaders have to do it to save lives and it's a fact that Flynn's actions in the War on Terror saved countless American lives. His men loved him as did his immediate subordinates. Those that didn't like Flynn were politicians like Obama who refused to call the terrorists, "Radical Islamists".
He's not a fuck up, IMO.