Several of our customers reported this problem.
Most of them had WooCommerce plugin installed & their WP_MEMORY_LIMIT low.
The solution is to increase your WP_MEMORY_LIMIT by following the steps below:
1. You will need to access your WordPress folder ( folder where you installed WordPress )
3. Right after the first line, add these two lines of code:
define( 'WP_MEMORY_LIMIT', '128M' ); set_time_limit(400);
4. Save the changes (and re-upload the file)
Take a look at the attached screenshot to see how it should look like.
Again, this error is not theme related.
It’s a standard procedure of increasing WP memory limit for WooCommerce plugin (and some others)
More information available at these links: