Your question is Reconciling an Exchange Invoice Discrepancy. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
Tell me about a time you found a discrepancy in a monthly invoice from an exchange or market data vendor. How did you investigate it, communicate with the internal stakeholders and the vendor, and drive it to resolution?