Touching the net with any part of the body or the paddle during play is loss of point. A player touching the net should promptly declare the violation and award the point to the opponents.
On rare occasions, a ball driven by a player into the net will force a loosely strung net to strike the paddle of the opposing net person, who may be crowding the net. If this occurs, it is loss of point for the net player’s team since the net was touched before the ball fell to the deck to conclude the point. (Moral – always tighten the lower net strings.)