Apple TV 1 gen turn off wifi (sleep)

HI

My apple TV 1 gen is turn off WIFI connect when i try to put some files on it (wifi). So i can’t even ping my apple tv. But i can use wifi from AppleTV (youtube and others).

If i connect Ethernet cable to my ATV from my Network hub all works (but this isn’t solution for me), when i disconnect cable wifi restore.

Where i can check this is sleep function of wifi or just overheat (or another).