Netflix is not responding?

I just watched a series on the TV via Google Chromecast. When I wanted to end it on my phone it did not work (see picture). So I unplugged Google Chromecast. But the ad is still there. What should I do?

I often had the problem with Amazon Music… Maybe just restart the phone.

Now the ad is gone, thank you

NetFix should also be enough to "Quit Force". This option can be found in the app info of Netflix.