"Don't panic. Maybe he hasn't picked it up yet. You could try to delete it before he sees it..."
Pick up – picked up – picked up
Meaning: If you pick something up, you collect it.
Grammar: This phrasal verb needs an object. It is possible to put the object between the verb and particle. If the object is a pronoun, it must go between the verb and particle.
Joe picked up the message
Joe picked the message up
Joe picked it up
He picked up - NOT CORRECT
Example sentence: Don't forget to pick those letters up before you leave the house.
Synonyms: collect, get
From: BBC Learning English - http://www.bbc.co.uk/worldservice/learningenglish/