I switched to BT Fibre Broadband from Vodafone Fibre Broadband last Wednesday. Plugged in the Smart HUB 2, connected my PC (wired connection), NAS Box (Wired Connection) and the families phones/tablets/laptops (WiFi Connections). Had a couple of IP address conflicts but soon sorted. All router setting remained at default (except passwords) All was okay Wednesday night, all devices getting to the internet, speed was good and the WiFi signal was good. Thursday morning, the PC could access the internet but the devices connecting by WiFi kept prompting for passwords and then saying the password was invalid. Additionally, I could not access the router's Hub Manager page from the PC. I restarted the router and everything started working. I decided to factory reset the router just in case and everything was okay. Friday, the same thing happened, the PC could access the internet but the WiFi connected devices could not. I restarted the router and everything started working. I double checked all the setting but could see nothing wrong. Once again I factory reset the router and all was okay. Saturday morning, exactly the same issue and I had to restart the router to get the WiFi devices to access the internet. Any ideas?
Make sure you have turned off smart setup in hub manager.
You need to try and avoid resetting the hub as it will be seen by the DLM as an unstable connection and result in increased noise margin and reduction in connection speed
It could be because of the firmware of the BT Smart Hub2
see this thread here