Alright, in all honesty: do you see the distinction between making an appointment and "occupying" a common space in a congressional office building?
“A group of people legally entered the Cannon House Office Building after they went through screening,” U.S. Capitol Police said in a statement to The Hill. “Demonstrations are not allowed inside Congressional Buildings, so when they started to protest and refused to stop, we began arresting them. Approximately 66 people were arrested for D.C. Code § 22–1307 – Crowding, Obstructing, or Incommoding – for illegally protesting inside the Cannon House Office Building.”
As it says in the first sentence of the police statement, they legally entered the building, so... Yes, you can legally enter the congressional offices to speak to your congressperson.
How do you picture people making requests for the government to do things in a world where lobbying is illegal? How do you see it being different from applying regulation of literally any kind?