I recently purchased a 65" Class 7 Series Smart TV. Everything was working fine for a day or two and I noticed that every time I would turn of my tv for a long time (one day to another), it would disconnect from Wifi. Googled this, was advised to do a soft reset (press and hold the power button) which successfully auto connects to the wifi but only for that day. The TV disconnects when I turn it off for that day.
I ended up exchanging the TV for a bigger one (75" Class 7 Series LED 4K UHD Smart Tizen TV Model UN75TU7000FXZA SKU: 6401719) because the TV expert from Best Buy said it was "the motherboard." Installed it yesterday, and today it disconnected from wifi. On both TVs, I performed the troubleshooting steps advised on other forums: soft reset, hard reset, reset router, firmware update, manually entered IP address.
do you have any other devices that connect via WiFi? are they experiencing similar issues? also check that your router isn't limiting the time a device is connected.
I find that my Galaxy S20 Ultra will sometimes lose connection to my WiFi 5Ghz after a couple days, but will stay connected to the 2.4Ghz frequency with no issue.
