Diagnosis
The TV's Wi-Fi module is losing its lease or encountering IP address conflicts, often due to router compatibility or the TV's power-saving features.
How to Fix It
Set a static IP for the TV on your router and disable the TV's power-saving Wi-Fi feature.
1. First, find the TV's MAC address in Menu > Network > Network Information.
2. Log into your router. In the DHCP settings, assign a static/reserved IP address to the TV's MAC address.
3. On the TV, go to Menu > Admin & Privacy > Power Mode. Ensure it is NOT set to 'Eco Mode' (use 'Quick Start'). Eco Mode can power down the network chip too aggressively.
If That Didn't Work
Change the TV's Wi-Fi band. If your router broadcasts both 2.4GHz and 5GHz with the same name (SSID), forget the network on the TV and connect it only to the 2.4GHz band, which has better range and stability for streaming.
Heads Up
Avoid placing the TV directly against a wall or in an enclosed media cabinet; this can severely degrade Wi-Fi signal. Ensure at least a few inches of clearance around the TV, especially on the bottom where the antennas often are.