How is the wifi signal strength where the SensorNode is not responding? I can’t see the wifi and signal information on the screen. It may be that the SensorNode sometimes fails to connect and send data before starting deep sleep again.
While in deep sleep the ESP is switched off and reboots every time, with consequent pink startup log, it’s normal if it doesn’t respond to ping during the sleep period.
As a first attempt to fix the issue, I suggest you connect the board to a PC, and through a serial monitor read the logs provided by ESPHome, it may be that there are problems in the connection/IP settings.
The use of a good power supply and cable can help as, during the wifi communication, the ESP32 has current peaks and brownouts can occur.
Another suggestion would be to disable the wifi power save from your configuration because it could affect wifi strength and you can also temporarily disable deep sleep so that you can identify the problem correctly.