in reply to modify the order a list with the help of a hash table

I try to remove all odor from my code, not just mask it.

Wait! You must mean sorting order...

@KEYS = sort @KEYS;

Assignment of the result is missing from your code.

Also, unless you have a logic issue (time not reported in 24 hour format) you should be able to string sort that time field directly.

$Hash{$Element[5]} = $Line;