The France international has come under fire this season following his below-par performances in the middle of the park.
Pogba has struggled to perform as part of a midfield pair alongside Serbia international Nemanja Matic.
The Red Devils signed Pogba in an £89m club record deal from Serie A giants Juventus in the 2016 summer transfer window.
The 25-year-old was dropped from the Manchester United team for their 2-1 aggregate loss to La Liga giants Sevilla.
His omission fuelled speculation that he could leave Manchester United at the end of the season.
However, former Manchester United captain Robson believes Pogba needs to make an adjustment to his attitude at Old Trafford.
“He’s on there (social media) a lot and he’s laughing and joking,” Robson told Irish radio station Newstalk.
“He likes to be in that limelight, coming across that he’s a laid back character and he’s jovial and he wants a bit of banter with the fans.
“For me though, it’s a little bit too much. You need to win. It’s not a game, so that’s where somebody like myself, Roy Keane and Graeme Souness, those sorts of people, a Gary Neville when he’s commentating, we understood that.
“This isn’t a game, this is our living and we need to win and I think Paul’s got to get that a bit more into his character. This is a job.”
Pogba scored two goals and two times in their opening four Premier League games before he suffered a serious hamstring problem.
The Manchester United record signing has gone on to score three goals and has made nine assists in 19 games in the Premier League this term.
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