Hello,
You can fix this problem by editing a query. Please follow these steps:
1. Open class/class-wcoa-attachment.php file
2. Around line number 117 there should be this query:
SELECT attachment.ID AS attachment_id,
attachment.post_date,
attachment.post_title,
attachment_meta.post_id AS order_id,
attachment.guid,
user_order.post_author
FROM %s AS attachment_meta
JOIN %s AS attachment ON attachment_meta.meta_value = attachment.ID
JOIN %s AS user_order ON attachment_meta.post_id = user_order.ID
WHERE attachment_meta.meta_key = '_wcoa_attachment_id'
AND attachment.post_type = 'attachment'
AND user_order.post_author = %d;
3. Change it to this:
SELECT attachment.ID AS attachment_id,
? ? ? ? attachment.post_date,
attachment.post_title,
attachment_meta.post_id AS order_id,
attachment.guid,
attachment.post_author
FROM %s AS attachment_meta
JOIN %s AS attachment ON attachment_meta.meta_value = attachment.ID
JOIN %s AS user_order ON attachment_meta.post_id = user_order.ID
WHERE attachment_meta.meta_key = '_wcoa_attachment_id'
AND attachment.post_type = 'attachment'
AND attachment.post_author = %d;