On occasion, I seem to have to move Unifi controllers or reconfigure APs altogether. So here's how I've done it since they always have issues with provisioning and adoption.
sudo set-inform http://10.0.0.2:8080/inform
default password to ssh is:
also, disable IPv6 on the controller so STUN doesn't have issues. Add the following:
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1