I have been having this issue with Fast Ethernet devices like my laptop, where the connectin drops automatically after like 13-15minutes. Having this issue since 21.02.1(previous versions not tested). I have tested this with two different laptops both FE, faced the same issue. Any idea why this happens?
Weirdly I have another router(10/100mbps;running openwrt 21.02.0) connected to this main router, no issue with it.
System Log
This happens continously and the laptop shows "cable unplugged"