Air Quality Monitor : (SKU: SEN0233) sensor values don't appear in Serial Monitor

HI,
I have some problems to display the sensor values. I don't LCD screen, just the serial monitor of Arduino IDE.
I used "Arduino Uno Wifi" with Expansion shield v7.1.
I used code of the wiki documentation, the differents step that I followed :

1. switch PROG/RUN of IO Expansion Shield to PROG
2. Upload
3. Switch IO Expansion Shield to RUN
4. Open Serial Monitor but nothing is displayed

nota: if I stay in RUN position and I upLoad, an error appears:
"avrdude: stk500_recv(): programmer is not responding"

Thanks for your help !