Problem after a night of idle

I noticed this morning, and have seen this a few other times, that I’ve lost all connections to my Pi during the night.
When I try to start LiveTV I get channel not available, and only spinning circle when I try to start any other video. And can’t connect with SSH.

I have external USB Wifi attached, and it shows activity.

I checked the connection screen, and it says online and a IP address. If I disconnect and reconnect I can play video and use SSH, but still not LiveTV. Need to reboot.

But how can I figure out why this happens?