Interested into this topic too.
After updating shelly 1L to 1.9.2 they stop to switch off light.
Tried with 4 1L... same result. They were all working (with button ad via application); later update them stop to work as expected.
I can hear sound coming from device as i press input into application; Device react if I switch off "operating light" (the red light into device) but it turn off power to system connected.
Roberto