chromecast wifi problems ??

[AC Question]

the google wifi dongle appears to have a major floor ! after casting through the dongle to my tv the wifi to my nexus 5 phone no longer works ! this problem has been ongoing for some time now - the dongle somehow overrides the settings on my nexus 5 phone - i find this very frustrating as i have to restart and readjust the phones settings to get the home wifi working on the phone again ?? i rebooted my phone twice and the problem still persists ! can anybody fix or help with this problem ? my guess is there is cross/connect problem with a shared wifi signal ??( the dongle and phone sharing the the same wifi signal ?)