had this issue for a while. after a couple of hours of rebooting my super hub 2ac. no new devices can join the network. although this seem not to effect apple devices. on both windows and android devices it connects but fails to assign an IP address.
I have reset the device to default settings and got a new Super Hub, yet it is still happening. the only way to fix it is to restart it. but it only works for up to 24 hours. any help would be appreciated.