It’s a common misconception that trafficking has to do with movement. It’s one part of one kind of trafficking but not the only thing. Per the official government website:

Neither U.S. law nor international law requires that a trafficker or victim move across a border for a human trafficking offense to take place.  Trafficking in persons is a crime of exploitation and coercion, and not movement.  Traffickers can use schemes that take victims hundreds of miles away from their homes or exploit them in the same neighborhoods where they were born.