The most common and most likely answer to this crossword clue is the 15 letter word UNACCOMMODATING
I've seen this crossword clue in The Guardian
U
N
A
C
C
O
M
M
O
D
A
T
I
N
G
Buddy explains!
The straight part
We know that "unlike 9 and 22" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case unlike 9 and 22 = unaccommodating.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 UNACCOMMODATING mean?
UNACCOMMODATING adjective- Not accommodating.