To expand on the two options above…
use Edit to change “Amount to make” without creating a duplicate. It just changes the original recipe once you hit save.
use Adapt to create a new duplicate recipe where you can change the amount to make. This method leaves your flavor percentages, but returns your Amount to make, nic and pg/vg levels to your default. You can change the title to include the new amount ml so you can have multiple recipes that have identical flavor%, but designate a different amount or different nic level or different pg/vg ratio for each.
Mongolian BBQ (this is the original)
Mongolian BBQ 120ML 6MG
Mongolian BBQ 30ML 2MG 50/50PGVG
Mongolian BBQ 30ML 2MG 25/75PGVG
(Definitely leave all of the duplicates private)
For a quick fix, though, just use Edit and hit save, for sure. Hope this helped!