There are no limits to how many lets a player can hit in a game of tennis. The server must repeat the serve until it is completed or be considered a fault.
There are countless let serves allowed throughout a game, and they are not limited in any way. However, you must remember that if the ball hits the net and does not land in the right service box, it is not considered a let serve.
Let Serve Rules
The International Tennis Federation, or ITF, states that “the entire point shall be replayed in all cases where a let is called, except when a service let is called on a second service.” The ITF has more detailed rules and guidelines available here.
If the ball hits the net, the band, or the strap and is good, or if it hits the receiver or the receiver’s partner, or anything they are wearing or carrying before hitting the ground after touching the net, it is generally considered a let.
It’s also known as a let serve when the ball is served before the receiver is ready. A service let does not count, forcing the server to serve again; however, it does not cancel a previous fault.
In a nutshell, if the ball touches the net and lands in the proper service area, it is a let. While the receiver is unprepared or uninterested, the server strikes the ball before hitting the ground or bouncing, the ball contacts the receiver’s clothing or body.
Conclusion
The players or the umpire can call the let during a match, and the number of let serves allowed in a single game of tennis is unlimited. Hopefully, this resource has given you a better understanding of lets and clarified some things for you.