The direct message inbox can be hard enough to spot on Instagram, especially with the one hundred and one changes the app has gone through in recent weeks.
But according to Cosmo, there's ANOTHER secret inbox that nobody knows about; just like on Facebook Messenger.
All you need to do to access your other inbox is:
Go into your messages, the icon on the top right corner:
If you have any secret messages waiting for you, there should be a blue note saying "Message request from" above your list of direct messages:
Now, click on the blue note and it will open up a list of your waiting message requests:
When you open these, you can select either to 'decline' if you don't want the person to be able to send you messages in future, or 'allow' if you do.