You got me there

you('ve) got me there

1. That is a question or problem to which I do not know the answer or solution. A: "The plan sounds good, but what do we do if the boss comes back early?" B: "Hmm, you got me there. Run, I guess." A: "What's the circumference of the earth, Dad?" B: "You've got me there, I have no idea!"
2. You have pointed something out that I am unable to explain, refute, or deny. A: "Yes, but isn't it true that you accepted campaign donations from several corporations that are lobbying against this proposal?" B: "Well, you got me there." A: "Don't you think this approach would be a much better use of our resources?" B: "Hmm, you've got me there. That does make more sense."
See also: there

You got me there.

Inf. I do not know the answer to your question. (Also with subjects other than second person.) You got me there. I don't know. You got me there. I have no idea what the answer is.
See also: there