Emergency Excel VBA Repair

My workbook relies on a VBA routine that pushes data from one sheet to another with VLOOKUP / INDEX-MATCH logic, but the macro has suddenly stopped running. No dialog, no error splash—just silence. I need the root-cause identified and a clean, working fix.

The code should once again:
• Trigger reliably (button, shortcut or Workbook_Open—whichever you find most robust).
• Pull the correct ranges, apply the lookup, and drop the results onto the target sheet without breaking existing formulas.
• Handle variable row counts gracefully so I’m not stuck editing the script every week.

Please return the repaired workbook or a standalone .bas module, annotated so I can follow the changes. If you spot any obvious performance wins—screen updating, calculation toggles—feel free to tidy those up too.

I’m ready to share the file as soon as we connect and will test the solution the moment it lands.