No problem 
The easiest way is to install Samba share through supervisor Add-on Store
Then browser with Windows Explorer to IP-address-HA\config\zigbee2mqtt
Open the configuration.yaml file (with notepad or notepad++) to change the pan_id and network_key.
- Hit save
- Delete coordinator_backup.json in the \config\zigbee2mqtt folder
- Delete database.db.backup in the \config\zigbee2mqtt folder
- Starting the Zigbee2MQTT plugin
- Reboot the system after a few minutes
- Reconnect the Zigbee routers to the mains
- Repair all your devices again