I’m not sure at the moment: do you have an inbound (-> incoming calls from the provider) or outbound (placing calls to the provider to call your neighbor e.g.) problem?
According your log, you seem to have a problem with the routing of incoming calls. You have to take care, that the inbound call is routed correctly through the inbound routes on base of the DID. You have to define the correct “Durchwahlnummer” in the inbound route and the desired device (“Ziel einstellen”) where to route the call to.
The “Durchwahlnummer” must be spelled correctly - I don’t know how 1und1 presents the DID (= your own number, which has been dialed by the caller) - Telekom uses +4989… e.g… Therefore you have to use those formats at the “Durchwahlnummer” field. This could be 004989 or 4989… or maybe something else. You will see this in the pcap trace, too.
If this doesn’t solve your problem: you have to describe, what you’re exactly doing and what you’re expecting to happen and what happens instead.