Originally Posted by
rcs85551
It's fairly easy. FRA and MUC offer TWOV (transit without visa) even for Chinese nationals.
Oddly enough, she transferred - without any Schengen VISA - FRA already four times ... twice on LH

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Assuming that the HKG-FRA-XXX was on one single ticket and the FRA-XXX flight was confirmed and within 24 hours of the arrival from HKG, this is a clear case of involuntary denied boarding & LH needs to properly compensate the passenger for the delay.
Her transfer in FRA was a fair bit less than 24h.