Ties up in changing rooms (5)
'ties up' is the definition.
The answer and definition can be both to do with contact as well as being verbs in their -s form.
Perhaps there's an association between them I don't understand?
'changing rooms' is the wordplay.
'changing' indicates anagramming the letters.
'rooms' anagrammed gives 'MOORS'.
'in' acts as a link.
Can you help me to learn more?
(Other definitions for moors that I've seen before include "Ties up (vessel)", "Conquerors once", "wild places", "wild areas", "Ties up a boat".)