Hey Pete,
thanks for your fast reply. Setting the interval to 60000 did not work and lowering it to 100 did also not work. Button Settings in the app are: Output D2 0 to 1 when pressed 1 to 0 when pressed again and the Button is in Switch Mode (Did try the Push Mode but it didnt work). Did also already try if(onoff == HIGH) but it didnt work either.