Study main light 3

This device is considered as OFFLINE by Zigbee2Mqtt.

Zigbee Id is unknown yet (did you restart recently?).
Address on Zigbee Network is 0x.
Link quality is unknown/255.
Model is unknown by unknown.
Hardware version is unknown.
Firmware version is unknown.
This device type is unknown

Rename
Only online devices can be renamed. You may try anyway, at your risk...
Warning: After renaming devices, you should restart Zigbee2Mqtt to force it to push new discovery entries. Renamed devices will appear "staled" until this reboot. THIS OPERATION WON'T CHANGE IDS IN HOME-ASSISTANT! Only the display name will change.
Configure
If the device is not working correctly, this will launch a new Zigbee Configure phase on the device.
There will be no feedback here for the outcome of the operation. This could also take few seconds.
If it's a battery-powered device, you should manipulate the device to force it to stay awake during the configuration process.
Binding
Bind this device (Study main light 3-) to send payloads (instructions) to this device:
See documentation here on binding. Binding to specific endpoint not supported yet. TIP1: You should manipulate the device right before sending the command to ensure the device will be awake and able to receive the binding instruction. TIP2: you may need to activate the report feature if you want the coordinator to receive new values. See how to activate the report feature here. You should check Zigbee2Mqtt logs to see if the binding/unbinding is successful.
Delete
Zigbee2Mqtt v1.7.0+
Note that a force remove will only remove the device from the database. Until this device is factory reset, it will still hold the network encryption key and thus is still able to communicate over the network!
TIP: Like for the Binding operation, it's better if you manipulate the device during the removal - unless if you're using the force remove mode. If you get an error during the non-forced mode, it means Zigbee2Mqtt wasn't able to reach the device.
This will remove the device from Zigbee2Mqtt. You may repair it if you need it again. Removing a connected device will probably cause the re-creation of the device itself.
TIP: removing a device could help solving connection issues by forcing Zigbee2Mqtt to rediscover the device.