United suffered their worst season in recent memory, losing in the Europa League final to Tottenham and finishing 15th in the Premier League.
Quickly after the season ended, Ruben Amorim and his lads flew to Asia as the club aim to claw back some money after failing to qualify for Europe.
Young stars Amad Diallo and Alejandro Garncho both got in trouble with the Ivorian giving a set of fans the middle finger.
Garnacho has also been accused of pushing a fan who was filming him walk through the streets of Kuala Lumpur.
United legend Beckham is disappointed, telling CBS Sports: “It's tough times. I don't like seeing some of the things that are going on at the club. On the pitch is what counts but in all honesty I'm seeing a lot of things that are not okay in my eyes as a fan and as a lover of Man United.
“You have to represent the badge. That's what it is about. I've seen a lot of things where players are not acting in the right manner.
“We were a part of a team that was so well mannered. We understood what it meant to play for Manchester United. We understood what the badge meant.
“Wherever we travelled, whether it was in Europe or in Asia, we respected the fans. We respected the fact that they were turning up, paying money and wanting you to sign and take pictures. You respect that.”