iPhone SE serial number

I have two iPhone SE (2nd Gen.) that I need to get the serial number. Normally, I would just look at the back of the device, but it seems the back of this model is just totally blank, with only the Apple logo, and no serial number. Also I thought about checking the settings, but an employee changed the passcode from our normal passcode. We have some remote software that can remove the passcode from our managed devices, but we need to know the serial number in order to do that. It seems I have a chicken and egg problem. Does anyone know how I can get the serial number in this case? I read that with some models, it is inside the SIM tray, but I didn't see it on this model.