1. Check whether the optical fiber connector on the optical cat is loose. If yes, reinsert it.
2, restart the light cat, cut off the power of the light cat, wait a few minutes, and then switch on the power.
3. The optical interface of the optical cat is faulty, and the optical cat needs to be replaced.
4. Your broadband bill is overdue. Now broadband is basically a postpaid model, because you owe money for so long, the carrier directly shut down your broadband, in which case you need to pay up to restore.
5, after the completion of the previous method, if the light cat is still flashing red, then it is recommended that you call the customer service phone of the broadband operator company, declare the fault, and let the operator company send someone to overhaul the broadband.