Undo

All sorted, I edited functions.php. Creating a new function and changing the image_default_link_type to ‘post’ as per below.

function mytheme_setup() {
// Set default values for the upload media box
update_option(‘image_default_align’, ‘center’ );
update_option(‘image_default_link_type’, ‘post’ );
update_option(‘image_default_size’, ‘medium’ );

}
add_action(‘after_setup_theme’, ‘mytheme_setup’);