There is a way to fix this as long as the train enters Germany on the same day as the arrival in Hamburg. @seewulf and @rvdborgt knows how to do.
You have to use 2 traveldays-also in the solution that anna mentions-as otherwise the app thinks you have 3 traveldays in DE=impossible. It boils down to making 2 trips: day 1 is fra Göteborg till Padborg/grenze-day 2 from there to home (may have to set manually)-train passes (and I hope you got that RES-it is really needed.
ALT: buy for 9€ and use nahverkehr fra HH till F=takes a long time, half of it have to stand crushed.
ALT-if NO RES: use the other DSB overnite fra K/obenhvn till Fredericia/Kolding-then onward from there=pass also border day 2.
You have to use 2 traveldays-
Yes 2 travelday but only 1 day in Germany. There is a way to do this by splitting the trip in 2 parts and then you only use 1 travel day, but I don't know exactly how to do.
I found the topic with the solution to your problem.
https://community.eurail.com/eurail-interrail-passes-41/inbound-night-train-problem-2751
Please ask if you need more advice.