Payment reminder / data based webhook

Payment reminder / data based webhook

Hello everybody, 

i wanted to setup a payment reminder when "due_days" reach a specific number, lets say 14 days.

I thought there is already a function like this and in the api documentation I could see that there is a function to turn on the "payment reminder" - whatever that is actually.

Anyway, I tried to setup a webhook which fires data once an invoice is overdue for 14 days. 
But whatever I set up, it doesn't fire and testing is very slow as I can only set times in 30-minute steps.

This is what I did : (and I have one invoice which is due_days are 14).