Why is the WiFi router intermittently without internet access?

Question

network hardware

Good afternoon. There is a tp-link wr841n v8 router, access to the network itself began to disappear. But with an interesting twist. After rebooting the device, wifi (like ethernet) works for exactly 2 minutes, then without access. Sometimes more time passes, he "comes to life" and falls again. I can't even imagine what causes such problems. I installed the latest firmware several times, changed the location of the router.
The Internet settings are dynamic, the mas address is own (from the factory), there is no binding.
The device is 2 years old, there were problems "without access to the Internet" several times, it was solved by rebooting.

Answer 1

Where are the logs, where are the diagnostics, where is the full description of the problem? Or should we guess? Your question is similar to this one: “I drive a car, sometimes it stops driving. I kicked the wheels. Wiped the headlights, it doesn’t help. How to make the car drive”