Comprehensive Excel Data Cleansing Task

I’m handing over a sizeable Excel file with 50+ columns spanning text, numeric, and date fields. It has grown messy over time and now needs a full hygiene pass. I need you to:

• Remove every duplicate record without losing any unique information.
• Re-format and validate each column so dates follow a single convention (e.g., YYYY-MM-DD), names and phone numbers share a consistent style, and numeric fields are all truly numeric.
• Identify and deal with blanks or missing values—flag them, fill them with agreed defaults, or mark them clearly for my review.
• Run a quick but thorough spell-check on free-text fields to catch obvious data-entry errors.
• Apply reliable sorting and filtering so the final sheet is logically organized and easy to analyse.

Please preserve the current worksheet structure; no data should be dropped except confirmed duplicates. Deliver the cleaned file back to me in the same Excel format along with a short change log that notes the main transformations you applied. Accuracy and attention to detail are more important than speed, but I’d still like to wrap this up promptly.