The most common and most likely answer to this crossword clue is the 2 plus 6 plus 7 letter word ON SECOND THOUGHT
O
N
S
E
C
O
N
D
T
H
O
U
G
H
T
Buddy explains!
The straight part
We know that "Reconsidering the matter" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case reconsidering the matter = on second thought.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.