what do I spend crysta on??

Hello I bought the game upon original release and purchased crysta to pay for my subscription. I canceled and came back recently and I have a good amount of this crysta left from my last time playing.
My question is what can U use this for now? it seems I no longer am able to use it to pay my subscription as the option is not there.

Thank you

You can buy stuff like minions, dyes, world transfers, name changes, and fantasia on Mogstation.

I'm not sure why you're not able to use it to pay for subscription though. As far as I know, that should still be an option as well.