webfont max-age=0

hi emre, i purchased your premium plugin a year ago and am using it with autoptimize.

the webfonts are here: /httpdocs/wp-content/themes/schema-child/webfonts/

now pingdom shows this: max-age=0 (woff2 about 57 kb).

the fonts show up nicely on our pages with or without caching.
but obviously they aren’t cached ?

how to cache the font? (there are: eot ttf woff and woff2).

thank you … thomas