Hi there, I have had the same issue. Dont know if you still need help.
Add this code snippet to your functions.php or Snippet plugin. This should work for you like it did for me. Had to do some digging to see what the CPT was called.
add_filter( 'generateblocks_do_content', function( $content ) {
$args = array(
'post_type' => 'adp-popup',
// Other args if you need them.
);
$posts = get_posts( $args );
foreach ( (array) $posts as $post ) {
if ( isset( $post->post_content ) ) {
$content .= $post->post_content;
}
}
return $content;
} );
