STM32F103C8 After Inactive Connection. #50

Hello guys, im trying to understand what happen here, i have module connected SPI in STM32duino, i recive a code in IR and send it with UDP Using OSC Message.

For a while works great, but in 2 hours or 3, the module goes to inactive in Router.
In Loop i have Ethernet.maintain();
The IP is static with Mac Address.

I debug connection R45 Plug with millis each 4 seconds. and apear connect, and IP show correct.