@Alexandr87 Hello, have you enabled the Wi-Fi Schedule on the C80? If yes, that would be the case that the Wi-Fi Schedule will enable both 2.4GHz and 5GHz at the same time. This has been reported to...

@SingletrackMind Oh my fault, I thought you're using Archer AX50, which some customers mentioned for AX3000. If yours is Archer AX3000, the beta firmware is not good to install. Are you saying you...

@Nolekor Hello, is there still a WAN IP address on the C80? Please go through the troubleshooting suggestions below to see if any works: https://www.tp-link.com/support/faq/1556/

@Rohit007 Hello, may I know how did you upgrade the router firmware? If you are trying to update it via the router web GUI, please be sure the router is connected to the internet fine, then it should...

@SingletrackMind Hello, you can try the solution we provided in the below thread, then report back if that works, thank you: https://community.tp-link.com/en/home/forum/topic/220212?replyId=1010732

@BackTrack5R3 Thank you very much for all the pictures and details. Are these tests made in the same environment, especially the same distance between the router and the phone, same obstacles, etc.?...