Are called in to put things in order (7)
I believe the answer is:
arrange
'put things in order' is the definition.
'arrange' can be an answer for 'put' (arranging is a kind of putting). I am not sure about the 'things in order' bit.
'are called in' is the wordplay.
'called' becomes 'rang' ('ring' can be a synonym of 'call').
'in' is an insertion indicator.
'are' placed around 'rang' is 'ARRANGE'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for arrange that I've seen before include "Set in place" , "Settle, work out" , "Fix" , "Orchestrate - order" , "Put in sequence" .)