Filtering out unwanted duplicate records

I think you need to first add a helper column that tells you which rows are candidates for filtering...

If you sample set is in A2:D5, then in E2 use formula:

=D2=MAX(IF($A$2:$A$5=A2,IF($B$2:$B$5=B2,$D$2:$D$5)))

adjust the ranges to ensure all data is captured.

Then you must confirm the formula with CTRL+SHIFT+ENTER not just ENTER. You will see { } brackets appear.

Then copy down.

TRUE results mean this is the Maximum for the combination in Columns A & B.

Then you can Autofilter for TRUEs and, if desired, copy/paste elsewhere.