In basketball, a player entering the court without reporting to the scorer's table commits an infraction. However, a technical foul should not be charged immediately if the ball is live, but should be addressed at the next dead ball situation.
In the game of basketball, all substitutions must report to the scorer's table before entering the court. If a player like A1 enters the court without reporting, it is indeed an infraction. However, the moment for the official to charge a technical foul depends on when the infraction was discovered. If the infraction is discovered after the ball becomes live, the foul should not be charged immediately, but instead should be addressed at the next dead ball situation. Hence, if an official charges A1 with a technical foul immediately after the ball becomes live, the official would be incorrect.
Learn more about Basketball Rules