@cayc When the Smart Connect is off, are you able to connect to the 2.4G or 5G network? Please check if you can still get a valid IP address from the router, try to do a ping test if the devices can...

@Yafi That's great to know that the issue was resolved by disabling IPv6 and SIP firewall on the router, we will certainly report this to the support engineers, and they will investigate. Do let me...

@rpotalara I see. It seems that your C60 is a BR version, I just noticed that it does support Onemesh already. As for the 2.4G not responding issue, have you tried my previous suggestions, do they...

@shubhro Try to follow this article to set up the router: https://www.tp-link.com/support/faq/1556/ May I know who is your ISP? Ensure you have internet access by connecting a PC directly to the ISP...

@DominikLulak Do you still use the original power adapter? Was there any power cut or bad weather or firmware upgrading before it behaves abnormally? Try to hard reset it by holding the reset button...

@SnehBansal I see. The issue had been escalated to the support engineers, they will contact you via email to investigate.