Mention inspector is a simple and helpful tool designed to check whether a certain mention is in the feed, to add it if it is not included, or provide an explanation as to why it doesn’t match a query.
Check out this article to find out more about Mention Inspector.
Also, learn more about the Mention inspector in the video below:
After you've opened the Mention inspector (by clicking on Help > Mention Inspector), select the query with the missing mention, and paste the URL of the website. To finish click on Inspect.
Pay attention to the URLs of Instagram mentions. You need to remove the slash "/" at the end of the URL for the Mention inspector to find your mention.