Originally Posted by
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It's most likely because Hertz at the Palma de Mallorca Airport is an Independent Licensee (according to Hertz.com) and doesn't honor Hertz reward days.
Almost certainly the case, but I've also had issues booking points rentals even at corporate US stores that very definitely should accept points. The system is very buggy.
If you have a reason to think the Mallorca locations should accept points, you might try calling Hertz and attempting to book a points rental by phone. Phone agents seem to be able to make it work even when the website doesn't.