SO is it CC0 (public domain)?
If yes, you should add the license into metadata for the asset packs:
"Edit asset pack->Metadata->Release Info->License for assets" It will increase the size of audience that will be able to find your art
Viewing post in Cute Wizard Asset Pack 1 comments
You chose CC-BY4 that requires credits... You can read more about cc licenses here https://creativecommons.org/about/cclicenses/
So is it correctly that it is CC-BY4?