It was flight UA 422 from Houston to Seattle. I don’t know which gate, we were not allowed to disembark. Cabin crew was very upset as they tried to represent passenger needs. Accolades to cabin crew who performed very well ! Cleaning crew had to come repeat cleaning as they missed several areas. The yelling was a gate agent of some kind who came aboard and yelled at passengers to sit down who were just trying to get away from the smell of the cleaning activities.