Major city hotel reported trouble (5)
I believe the answer is:
hanoi
'major city' is the definition.
'Hanoi' can be an answer for 'city' (Hanoi is an example). I'm not certain of the 'major' bit.
'hotel reported trouble' is the wordplay.
'hotel' becomes 'h' (phonetic alphabet: alpha, bravo, charlie etc.).
'reported trouble' becomes 'anoi' (I can't explain this - if you can you should believe this answer much more).
'h'+'anoi'='HANOI'
Can you help me to learn more?
(Other definitions for hanoi that I've seen before include "Asian city" , "Capital city of Vietnam" , "Vietnamese city" , "Asian capital on the Red River" , "capital out East" .)