Hi friend.
1. The authentication information such as the SN and physical address of the ONT/ONU conflicts with that of other users. The OLT deactivates the ONT/ONU that goes online last.
2. The loop detection function is enabled on the OLT, and a loop exists on the ONT/ONU. After detecting the loop, the OLT deactivates the looped ONT/ONU.
3. The line quality of the ONT/ONU is poor, and bit errors increase greatly. As a result, the ONT/ONU is deactivated.
4. Run the deactivation command to manually deactivate the ONT.
Thanks.