Missing Contacts List Comparison

I have two separate customer-contact spreadsheets that no longer line up. Your task is to compare them side-by-side, using Full Name as the sole matching key, and clearly identify every contact that exists in one list but not in the other. Accuracy is crucial because these files feed different parts of our sales cycle.

You’re free to work in Excel, Google Sheets, Python (pandas), or any similar tool—whatever lets you deliver a clean, verifiable result fastest. I’ll supply both raw files as soon as we start.

Deliverables should arrive as:
• A new sheet (or CSV) containing only the missing contacts, flagged by which original list they were absent from
• A brief note on any name-format inconsistencies you had to normalise so I can replicate the process later

If you automate the comparison, please include the script or formula for transparency. Accuracy beats speed, but hitting the next business day would be ideal.