I think you may have misunderstood what Lumia was trying to say.
What I understood was not that
Lydia was mispelled in general (it may be a correct spelling in another language), but rather that in Spanish the proper spelling is
Lidia (and
Araceli, etc). At times you will find it spelled with a 'y' just like you see names mispelled in English. Example:
Ashlyn instead of
Aisling.
That's what I understood anyway.