One falsehood I just ran into myself when booking a parking spot at the airport: "all parts of a name start with a capital letter". This isn't true for Dutch names with "van de", "van der" etc, which this site "corrected" to start with capitals. So silly to have a system "correct" my own name and get it wrong.

This happens to Irish/Scottish names too, such as McDonald, Mc being 'son of' in Gaelic language; the capital letter after Mc is wrongly changed to a lowercase letter.

Another very frustrating issue I run into, is hyphens not being allowed. My firstname and surname both have hyphens, and they are very common even in English based names.