It's because they have different sounds despite using the same letters. For example, the "e" in
Alice isn't pronounced, it's "eh" in
Celia and "ee" in Lacie. This applies for
Aidan,
Diana and
Nadia. They all use "i," but the letter makes a "yuh" sound, "I" sound and "ee" sound, respectively.
In each of the OP names the "el" sound appears, and in two the syllable "bel," which makes them obviously anagrammed.