Error: The account owner has disabled access to Instagram Direct Messaging

The error "The account owner has disabled access to Instagram Direct Messaging" occurs when access for third-party apps to direct messages is disabled in the settings of a professional Instagram account.

The access may have been accidentally revoked by the account owner, or the authorization session/access token may have expired or been reset on Meta's side.

To fix this error:

1. Open the Instagram app on your phone using the required account.
2. Go to your profile and tap the menu (three lines) in the upper right corner.
3. Select "Messages and story replies".
4. Tap "Message controls" or "Message requests".
5. Find the "Connected tools" section and toggle on "Allow access to messages".