It looks a bit like OOT's
Surrounding Curls Hair for Genesis 3 and 8 Female(s) | Daz 3D
https://www.daz3d.com/surrounding-curls-hair-for-genesis-3-and-8-females
...which is used here for a different Addy promo at rendo but is actually credited.
I was looking for similar.
It could be tweaked to be more curly if included in the style dials.
Or it could be a mashup of a couple things. (Which seems to possibly be the case often with that vendor and their promo hairs. Many of the Addy promos have hair very different looking on the whole from anything available, but sometimes in those cases have elements definitely traceable to one or two known assets. The Lyla promos, for example, were suggested to be a mashup of OOT's 2022-03 Hair and Bendine Hair in a forum thread somewhere.)
Have you tried contacting Addy?
I find that if asked nicely (and if they're not too busy) vendors answer such in turn sometimes.