Halo isn't a technology, it's a benefits package add on. What technology have you upgraded from and to? Have you got a new hub, did you remember to turn off Smart Setup? Turn off the 5Ghz wireless and once the camera has connected turn it back on again.
Yes I've got a new hub .not sure what my old1 was tbh .how do I turn the 5g off ? My son set it up for me so as for the smart set up being turned off I haven't a clue sorry .
Put 192.168.1.254 in your browser address bar to access the hub manager. Smart setup is on the front page. If turning that off doesn't work, go to Advanced settings and then wireless to turn off 5Ghz