Screen cast (mirroring) not working

[placeway]

I have both a Pixel 3 and an Essential, as well as a Roku Ultra. Both phones are stock on their latest version of 10. On the Essential I can pull down the quick settings and turn on Cast Screen and the Roku is found and I can mirror my screen. Attempting the same with the P3 results in no device found. However Google Home finds the Roku, and if I tap the cast icon in media apps like YouTube or Netflix the Roku is found. Just not when I try to screen cast/mirror with the P3. I've tried restarting the Roku, the P3 and the WiFi router to no avail. What could be wrong? (I just got the P3 a month ago used, and today was the first time I tried screen casting with it.) Thank you in advance.

 

[patruns]

I can cast any screen after opening the home app, choosing the device (in my case Chromecast) and tapping "cast screen". Now whatever screen I go to it is mirrored to Chromecast. You can't do it from the pull down shortcut menu. You have to do it from within Google Home.

Note, this is different from casting via the Chromecast icon in media that supports it.