This has turned out to be a complete disaster.

There was no way the journey could be executed because by the time you're through immigration check in is closed.

I've had to buy a very expensive o/w ticket with KLM to an airport near my original destination just to get home today.

I've abandoned my luggage in DUS because the gate agent there said it hadn't been loaded in IST. (I can now see from my airtags that it had been.)

What a mess. It's an LH-issued ticket so I'm trying to get though to the SEN line at the moment.

I guess I'll have to visit the original destination airport in person later in the week and give them my luggage receipts?

Anyone have any tips?