So if your flow doesn't do what you want think it should do it is worth putting more debug nodes in it, so you can work out where your flow diverts from what you think it should be doing, so I would have debug nodes after every change and switch node to allow me to see what is happening.
There are several different ways of doing what you want.
What I would do is to use your BigTimer node to set a global variable using a change node
(eg Set global.lightSwitchWork to msg.payload)
You can then use a switch after your "Licht ein" to check for this on only pass on a message if allowed by the global variable eg global.lightSwitchWork is "On"