Solution:
Step :1 Edit your wp-config.php file and enter something like:
define('WP_MEMORY_LIMIT', '256M');
Step :2 If you have access to your PHP.ini file, change the line in PHP.ini
memory_limit = 256M ;
A complete referance regarding (It works for WordPress and woocomerce issue ) :
https://docs.woocommerce.com/document/increasing-the-wordpress-memory-limit/