Don't take my word for it. Ask it: "How many people are wearing tennis shoes in the United States right now?"
The response I got: "I'm sorry, I don't have the current data on the number of people in the United States who are wearing tennis shoes right now. It's not possible to determine this number as it would require constantly monitoring the footwear of every person in the country, which is not feasible. The number would also vary greatly from moment to moment and would be influenced by a number of factors such as time of day, weather, and location."
No hallucinations, no bullshitting. Just "I don't know" and an explanation of what it would take it find out. No idea why you think it has trouble expressing a lack of confidence in its answers.