Press the doorbell. If the doorbell does not ring, please power up the doorbell first and make sure it is not low on battery.
If the doorbell rings but the chime doesn't, the doorbell and the chime are disconnected. To fix this, you can try pressing the doorbell a few more times. If this doesn't work, you can reboot the doorbell. If this still doesn't work, you can reboot the chime by unplugging it from the socket and plugging it back in. Rebooting the chime takes about 3 minutes.