The most common and most likely answer to this crossword clue is the 7 letter word BILIOUS
I've seen this crossword clue in The Times
B
I
L
I
O
U
S
More clues leading to the result BILIOUS
Buddy explains!

The straight part
We know that "Unsettled" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case unsettled = bilious.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.
What does BILIOUS mean?
BILIOUS adjective- Of or pertaining to something containing or consisting of bile.
- Resembling bile, especially in color.
- Suffering from real or supposed liver disorder, especially excessive secretions of bile.
- Peevishly ill-humored, irritable or bad tempered; irascible.