My favorite is when it bounces back and forth between the same two wrong answers, each time admitting that the most recent answer is wrong and going back to the previous wrong answer.
Doesn't matter if you tell it "that's not correct and neither is ____ so don't try that instead," it likes those two answers and it's going to keep using them.
The false info baked into its context at that point in the conversation and it will get stuck in a local minima trying to generate a response to the given context.