wysiwyg Editor for metafield not working

Hello Support,
I have used the plugin Custom Metadata Manager in my WordPress site. I have try to get the Editor in my custom post type using the below code:

x_add_metadata_field(
‘fsdescription’,
$post_type,
array(
‘group’ => $gg, // the group name
‘multifield’ => ‘featuredstories’,
‘description’ => ‘Story Description’,
‘label’ => ‘Description’, // field label
‘field_type’ => ‘wysiwyg’,
)
);

But it is not working. So Kindly help me to fix this ASAP.

Thank you

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