voltage sensor unstable in my code

I'm sorry spycatcher2k I'm still new here and also with Arduino programming
I attached a file with my code

hello outsider the sensor reads up to 25vcc and it's great for me this value I'm going to work with something around 12vcc follows a link from the sensor https://www.ebay.com/itm/2pcs-Standard-Voltage-Sensor-Module-For -Robot-Arduino / 261961157472? Hash = item3cfe1a0b60: g: FdQAAOSw-vlVnncO

my code.ino (4.64 KB)