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I have a one way ticket from BKK-TXL with stopover in CGN. I would rather get off in CGN and start my land travel in Cologne going to Amsterdam and other parts of Europe, instead of landing in Berlin. So I would like to miss my CGN-TXL leg on purpose. Is this okay?
Addendum: I will have no check-in baggage and do not have a return flight. The CGN-TXL is my last leg. Looking at the answers below, seems it is okay for me to purposefully miss the CGN-TXL leg. So thank you everyone.