Why is the Netflix app constantly disconnecting from my Chromecast?

Why is the Netflix app constantly disconnecting from my Chromecast?

Because you have wrong attitudes

But there's no setting where you can set the Netflix app to disconnect from the Chromecast

Almost the streaming from the app on the smartphone to the Chromecast?

If so, maybe you have too many Wi-Fi connections stored, went to a friend like that. When she then deleted some wireless connections, it worked again smoothly. Also check if the app is up to date, maybe there's an update, what you should install.