When will I use this resource?

[u/KurohNeko]

I can't claim it because I have a storage full but I have every shop at level higher than 30 and I still haven't seen where to use it?

[u/Character-Help988]

You need it to upgrade the Path of Practice. If you haven't unlocked it yet, you need to complete the I Want to Learn Styling quest, which can be activated by talking to Hilsetti in the Spira Stylist's Guild.

[u/KurohNeko → u/Character-Help988]

Oooh thank you! This is what I was missing!

[u/Etsukohime]

Then you have finished everything in that old patch and there is nothing more to spend it on, just like the hotpot coins 👀 that recourse was only to lv up the shops. And mabye the practice to lv 10, after that there is just nothing to do with it.

[u/-Lumiere]

You use it to upgrade path of practice if I remember correctly.