memory error

This plugin is really great, but I’m getting a repeated error in my logs, I’m not overly knowledgeable in code but maybe you have some idea what is causing this? Maybe it’s one of my settings?

[lsapi:error] Backend fatal error: PHP Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 2266816 bytes) in

… wp-content/plugins/wp-fastest-cache/inc/css-utilities.php on line 267\n,

my site is petluck.ca

thanks!