I had to tweak this article as I was only using 2 columns (email and login date)…
Here’s what my formula looked like (I used excel tables), pasted in column F
XLOOKUP(MAX(Table2[Login Date/Time (UTC)]),(Table2[Email]=E2)*Table2[Login Date/Time (UTC)], Table2[Login Date/Time (UTC)],,-1)
the E column listed unique email addresses.
The source table which had multiple date/times per email was in column A ([Email]) and column B ([Login Date/Time (UTC)])
Article: https://exceljet.net/formula/xlookup-latest-by-date
