Use of undefined constant Error

Check your wp-config.php file. Is there a line containing “256M”? If so, what is it?

define('WP_MEMORY_LIMIT', ‘256M’);

This is the line which is triggering error.

Remove and retype that line, making sure you’re using the right delimiter ', as it doesn’t look like that’s how it’s currently typed.

thanks @sterndata

issue is fixed