manual switch not opperating shelly relay

  • Hi ,Im in the US and this is my first shelly switch .

    I have led lights behind a dimmer switch. the app turns the lights on and off but when the switch is turned on nothing happens. the switch works normally in the circuit without the shelly. I have tried another switch with no dimmer and the shelly works as expected from the app and the switch.

    there are a lot of these switches in my home so I am hoping someone has an idea of what is happening and how I can use these switches. thanks