两个不同的WordPress帖子，两个不同的ID，但有相同的slug

Question

I'm stuck with some strange problem , Whenever user search for a post it first looks on a post , if a post is available it show the post but when post is not available it creates new post via code and gets the post content from other sites API . So everything is working perfectly until I find that there are some post whos have different ID but their slug are same and when I open that post. WordPress single.php show the content of both page at same time.