The most common and most likely answer to this crossword clue is the 9 letter word WARRANTEE
I've seen this crossword clue in The Times
W
A
R
R
A
N
T
E
E
Buddy explains!
The straight part
We know that "Customer expecting protection" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case customer expecting protection = warrantee.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 WARRANTEE mean?
WARRANTEE noun- The beneficiary of a warranty.