The most common and most likely answer to this crossword clue is the 6 letter word NOSHOW
I've seen this crossword clue in Financial Times
N
O
S
H
O
W
More clues leading to the result NOSHOW
Buddy explains!

The straight part
We know that "She doesn’t appear" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case she doesn’t appear = noshow.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.