This issue will be fixed by software update. For how to update, refer to: How do I perform Firmware/ Software Updates for my Android TV™?
If you cannot update the software, restart the TV.
How to restart (reset) an Android TV?
The issue may occur repeatedly if the TV is off and the connected Wi‑Fi network is lost.
In such cases, check the following.
- If a power-saving feature in the router stops the Wi-Fi signal periodically, turn off the feature.
- If you manually turn off the router, always keep it on instead of turning it off.