It might because of many reasons:
- Fan 1 is not connected to the Program (via Bluetooth, WIFI, or wired)
- The code made to make Fan 1 start up has a bug or an error
- Fan 1 has a hardware problem
- Fan 1 is out of reach for the electronically controller to reach
- Fan 1 is not connected to a power supply (tho)
sorry if my answers don't help solve your problem
