@TP-Link Hello, Thank you for your answer. It's working fine now. I've waited 3 or 4 hours, reset again the second deco and tried again and boom! Working again. All I can see is that yesterday...

I have two Deco M4 setup as Access Point. Main Deco is connected directly to my router, second one is connected using Ethernet Backaul. Everything was fine since I bought them. This morning I have...