YouTube cast icon disappeared

Basically a Chromecast will allow you to add any TV (well at least the ones new enough to have HDMI ports) to your home network. A Chromecast has its own wireless chip inside so once added to your home network it's just another device, like any laptop or computer or smartphone, with its own IP address. If you have a Smart TV, you probably don't need a Chromecast, the TV will have its own wireless capability built into it so you can just add your TV to your home network (that's a part of why it's referred to as a 'Smart' TV as opposed to just an older, conventional TV.) If you have pretty dated TV, that doesn't have any HDMI ports, a Chromecast won't be of much use. In that case look at getting a Roku Express+, one of the few remaining set top boxes that still support composite cables (those cables with the yellow-white-red jacks on each end).
https://www.roku.com/products/roku-..._medium=rokublog&utm_campaign=rokuexpressplus

But from what you've described you at one time were able to cast and now cannot so it sounds like your TV and your Nexus just aren't on the same local network anymore. Have you changed to a new wireless router recently? Or reconfigured your existing one in some way? Or move your TV to another location? Something changed so not all your devices are on the same network like they once were.
Install this network scanning app, Fing and do a basic scan of your home network:
https://play.google.com/store/apps/details?id=com.overlook.android.fing&hl=en
You should see all the different devices connected to your network -- your router, any laptops or computers, your Nexus, and your TV (or Chromecast if that's what your TV is using to connect). If you do see everything, than there's a different problem, but if not you need to get your TV and your Nexus back on the same network.

I'm having the same problem. I have a Roku and a Motorola G7 Play. Usually I have the option to cast to device, but recently it's been disappearing from my YouTube app. I downloaded the network app recommended above, and it shows that my phone and Roku are on the same network. But when I try to cast anything (even with a separate app) it doesn't register that my Roku is there.

LordFahren said:

I'm having the same problem. I have a Roku and a Motorola G7 Play. Usually I have the option to cast to device, but recently it's been disappearing from my YouTube app. I downloaded the network app recommended above, and it shows that my phone and Roku are on the same network. But when I try to cast anything (even with a separate app) it doesn't register that my Roku is there.

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from time to time netflix or youtube will do this. if i close the app, clear cache and sometimes reboot my phone, i will regain the cast function on both apps. you might want to try that and see if that helps.

ocnbrze said:

from time to time netflix or youtube will do this. if i close the app, clear cache and sometimes reboot my phone, i will regain the cast function on both apps. you might want to try that and see if that helps.

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I've already done all of these. None of them seem to work.

i do not have roku, is there an app associated with it? have you tried clearing cache for that? maybe delete and re-install the roku app. was this all of a sudden? or after an update on either the phone or the roku app?