**Enable messaging here 



Instagram messaging connection settings are only available for Instagram accounts connected to Facebook Pages, Facebook Business Suite, Pages Manager App, Business Manager, Creator Studio or third-party apps.

You can control your Instagram messaging connections across different apps. If you enable access to Instagram Direct Messages, you can view or send Instagram Direct Messages on Facebook Pages, Facebook Business Suite, Page Manager App, Business Manager, Creator Studio, or other third-party apps you use to manage your account. If you disable access, you can only view and send Instagram Direct Messages from Instagram.

To manage your Instagram messaging connections across apps:

  1. Go to your Instagram business or creator profile.
  2. Tap Menu.
  3. Select Settings.
  4. Select Privacy.
  5. Select Messages.
  6. Under Connected Tools, you can toggle on or off “Allow Access to Messages.”
    1. If you toggle on, anyone with approved access to your Facebook Business Suite, Creator Studio, or other connected third-party apps can view or manage your Instagram Direct Messages.
    2. If you toggle off, you’ll only be able to view your Instagram Direct Messages on Instagram.

Now, you’ve finished setting your Instagram messaging connections across apps. You can go back and change these settings at any time. You can also manage your Instagram messaging access in Facebook Business Suite and Creator Studio.


Source: https://www.facebook.com/help/instagram/791161338412168