Go bug

Go bug occurs when you try to enter a battle at an enemy gym, but after the word ‘Go’ you get kicked out of the match only to return to the gym’s stat screen. This usually happens after you’ve restarted the game because of the 1HP glitch, the server thinks you’re still in the battle and thus doesn’t let you start a new one. Just wait for a minute or two and try again. Usually the server kicks your ‘ghost’ out after the battle timer (which is also desynchronized) on the server has ended.