Alula formula

My bub is 6 months and on alula gentle formula,, she's been having 180mls (max amount on tin) since 4 1/2 months and lately will cry and fuss after finishing bottles like she's still hungry. Can I make bigger bottles following the ratio of water to formula? Just confused as this amount is supposed to be enough from 4months to 12months.

Add-She is combo fed but only has boob to sleep for naps and overnight as I'm an under supplier and only make 80ml combined so she also has 40ish MLS of breastmilk every 2/3 hours for naps