1.
If you mess something up or if you mess up , you cause something to fail or be spoiled. ( INFORMAL )
When politicians mess things up, it is the people who pay the price...
He had messed up one career...
If I messed up, I would probably be fired.
PHRASAL VERB : V n P , V P n (not pron) , V P
2.
If you mess up a place or a thing, you make it untidy or dirty. ( INFORMAL )
I hope they haven’t messed up your video tapes.
PHRASAL VERB : V P n (not pron) , also V n P
3.
If something messes someone up , it causes them to be very confused or worried, or to have psychological problems. ( INFORMAL )
That really messed them up, especially the boys.
PHRASAL VERB : V n P , also V P n (not pron)