How can I turn off my buzzer esp32?

Hello, I was working on a small project with my esp32-Wroom-32 and I manage to turn on the board with a buzzer attach to it with the help of my cellphone my question now is how can I turn off my buzzer with the help of my phone? Here is my code so far .

The easier you make it to read and copy the code the more likely it is that you will get help

Please follow the advice given in the link below when posting code , use code tags and post the code here