The following guide is intended for most Yealink devices, however, the troubleshooting steps can be applied to almost any device.
When a phone says "No Service" it usually means that the device is not connected to the internet. This can be checked by seeing if the device has an IP Address.
The IP Address can be found by pressing the OK button on the default screen. This will pull up a set of information titled "Status". If it doesn't have an IPV4 address, then the phone is not connected to the internet.
Troubleshooting Steps:
1. Try Disconnecting and Reconnecting the phones to where they are currently connected. This is usually an Ethernet Cable plugged into the back of the phone into a port labeled "Internet". It could be a loose connection. Once connected, check the Status screen again by pressing the OK button on the default screen.
2. Try plugging the phone into the location of where a working phone is. If the phone works and obtains an IP address at the other location, then the issue may have to do with where the phone is being plugged in to and not the phone itself.
Compudile phones require the internet to work so a working internet connection is required
We would recommend trying to use a different cable or reaching out to a 3rd party that can check the cabling for any wall ports in your building.
Remember, since Compudile's phones run off of the public internet, the same ethernet outlet the phones plug in to can be used for any internet device, such as a TV, Computer, or Printer. As such, Compudile is unable to assist in checking building cable connections.