If the "write to table" function isn't working on a specific column, here's what you can try:
1. Delete the affected column named "4".
2. Create a fresh column with a new name (avoid special characters).
3. Re-map your data to the write-to-other table.
Make sure auto-dedup is activated in the destination table. If the issue persists, try using the Force Run option in the table settings, which may take some time depending on your table size.
Remember, you can map individual values or entire lists when using the "write to table" function.