I have a Tapo C520WS camera. It has been working for 2 years without any problems.
To be clear, it was not powered by its original power supply, but through a UPS, because there are frequent power problems in my country.
However, the power supply voltage is stable at 9-9.5 volts.
It worked without any problems for two years in this mode, connected via Wi-Fi.
But recently, problems with Wi-Fi disconnections began. At first, it just disconnected, but the camera continued to work. Then it disconnected and the red indicator flashed. It helped to simply disconnect it from the power supply for a couple of minutes and then reconnect it.
Then once I had to completely reset the settings and reconnect it, because nothing else helped.
And now nothing helps at all. I turned it off, reset the settings in various ways, nothing.The MicroSD card also has no effect on the result.
The indicators flash red and green, the camera says that the settings have been reset, but the camera does not create an SSID. None of the three smartphones can see Tapo_Cam_XXXX.

I don't know if this is a direct cause or not, but these Wi-Fi problems started with the change in weather, when the temperature outside dropped below -20 degrees and reached about -27.

So I took the camera off the street, hoping that it would warm up in the heat and start working, but no, that doesn't help anymore.

I tried checking the cable connection, and it works fine via Ethernet cable.
So it turns out that only the camera's Wi-Fi module has failed.
 

My question, is there a chance to try to fix this with software? Maybe update the firmware or something other than a standard reset.
 

I don't want to return it under warranty because I'm sure it will take a long time, and there is a possibility of a “non-warranty case.” I'd rather spend some time and wire it up if there is no software solution.

In addition, I have a Tapo C320WS, which works in the same mode, and I have never had any problems with it.