Gzip pllugin’s cache file

Is there a way to Gzip your cache file to improve pagespeed score?

I see this under “Enable gzip compression” when testing with GTmetrix:

…./wp-content/cache/wpfc-minified/g1h7u1fv/9tqok.css

and it is the only one GTmetrix suggests to be Gzipped. Normally, other pages and posts on my site score above 90. But several others just score around 50 or even lower, and the thing spotted is normally the cache file from the plugin.

Do you know if there is any way to deal with it.

Many thanks.