A technical 'glitch' caused a temporary shutdown.
computer/software 'glitches'
(..) Cole. Cole. Jesus. Deacon, what? It's Cassie. What the hell's going on? Nothing. A glitch in the system caused by the damage to the Core. Cassie... Tell him. What is this? The tether... it disengaged itself from the system and then reappeared... some kind of glitch. It's entirely unnecessary to maintain her tether. All that matters is that she arrived. Hey! Tell him what you did. Clearly, Dr. Railly (..)2016 TvShow: 12 Monkeys Title: Lullaby Season: 2 Episode 8