The serial number is located on a sticker at the top of the camera. In the S22WA model, it is found inside the front cover. You can see a sample of the sticker below.
The serial number consists of numbers as well as uppercase and lowercase letters. In the example image, the serial number is FEa118Fp00271. The serial number provides information such as the camera’s manufacturing date, production batch, and model identifier.
To check the manufacturing date, you can find more information here.