I believe this is a hosting problem, not a plugin problem. Search for this error on google and you will find a lot of info.
Here’s how to increase your memory allocation in WP https://codex.www.ads-software.com/Editing_wp-config.php#Increasing_memory_allocated_to_PHP This may or may not work, depending on your hosting provider. Note that there is a big difference between your storage (disk) space and your max memory allocation. I would imagine that the 25GB you mention is your storage space. (?)
You can probably avoid the issue entirely by installing the plugin “manually” – download the plugin from the WordPress Plugins site to your PC, then FTP it up to the plugins directory of your WP site. See the “Installation” section of the plugins WP page.
Good luck.