Failed zu route to Sylt via Syltshuttle (train)

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So there are two ways to enter the german island Sylt.
First is with the ferry, ABRP can handle this already.
Second is via SyltShuttle. This is a train that starts in the city Niebüll and ends in the city Westerland on the island.
No tricks, like dont drive over the border of Denmark worked.
So can you give ABRP the possibilty to use the train for future plans?