Increase is contrived (3,2)
I believe the answer is:
put up
'increase' is the definition.
(thesaurus)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for put up that I've seen before include "Offer one's home" , "Build - house" , "unfair sort of job" , "Have to stay - bogus" , "Give accommodation to" .)