Net and Wall Violations

A player, their racket, or anything worn or carried touches the net, net posts, the tension cable, or any part of the opponent's court while the ball is in play — loss of point (Rule 13.1.a).; If a player returns the ball off the walls of their own court but the ball then hits the net or net post...

Source: Rule 13.1

Send this to your friend — argument over.