Issue with serial monitor

I have an issue with serial monitor that doesn’t show anything.
I checked all the topic related to this problem but could not find solution.

I have a ESP32S3, I just download a program for led blink and put some Serial.println(“test”)
the led blink, but noting on the serial monitor.

I was working before on an ESP32 and it was working.

Well with an ESP32S3 it can be that you have used a board definition file that outputs it stuff via UART while it should go out via USB CDC, or the exact reverse case. Without knowing what physical board you have and what your platformio.ini is, that’s impossible to answer.