AVM Fritzbox tools integration call deflections

I just play around with the call deflection. On lovelace by default I see nearly 30 Buttons for it. Tried to configure two of them to forward calls either to my wifes or my Mobile phone. For that I first configured my Mobile for deflection within the Fritzbox 7580 and after that the same for her Mobile. The second entry overrides the first Mobile record. I wonder if it is only possible to have one configured at a certain time in the Fritzbox and why there are than more than one Button for that within Fritzbox Tools?
Is there someone out here, who has more potential deflection configured in the Fritzbox in parallel ?
I’m just a little bit lost.