If your lights don’t go off either switching it from the app or from the device itself, the reason could be that you connected the iotty Light Switch to a load too big, unfortunately the situation cannot be restored.
Next time be sure that the loads respect the device parameters (input 110-230V~, frequency 50-60Hz, max 5A).
Be aware that if it happened to only one gang (and you have a iotty Light Switch with multiple gangs) it doesn’t affect the others, so you have the possibility to use another gang for the same contact after changing the load and then disable the non-working gang.