For LOS (Loss of Signal) red lights on fiber or advanced gateways, it usually means the incoming optical line is not detected or has low signal. Double-check that the fiber line is connected properly and that there's no bend or physical damage. When it's green and steady, everything is fine. However, when it blinks red or stays solid red, it signifies a Loss of Signal, a problem preventing your router from communicating. Troubleshoot your router's red light with these steps. A red light on your router can be a source of frustration and confusion. Fortunately, diagnosing and resolving these issues doesn't have to be. Turn off the power of the Mi router (press the Reset button to close the router and remove the power), and try to restart it to see if it can be restored to normal. Before you panic or call tech support, there are several simple fixes you can try at home that often solve this problem in minutes.
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