What exact Zigbee Coordinator adapter model? Sounds like it is a previously used Zigbee adapter that already has a existing Zigbee network configured on it since before. Suggest that you reset it to remove any previous Zigbee network, and also consider flash a later firmware before start to use it if it has an older firmware. If you are not trying to migrate from a other installation or platform then you should use a Zigbee Coordinator adapter that does not already have a formed Zigbee network.
You should be able to reset it with either TubesZB Zigpy-CLI Tools add-on or use zigpy-cli directly, see: