Agents are unable to respond to an Instagram Direct message in Support.
Only the assigned agent can join a live Instagram Direct conversation.
For steps on how to assign a ticket, see the article: Manually assigning a ticket.
If the assigned agent is unable to respond to the message, then they must be enabled for Chat. Depending on your role, you can update the agent's permissions in a few ways:
For Support admins
- Open Admin Center and navigate to the Team members page.
- Search for the affected agent, and open the agent’s profile page.
For more information, see the article: Setting roles and access in the Admin Center.
For Chat admins
From the Chat Dashboard, navigate to Settings > Agents > Add agent.
For more information, see the article: Understanding default roles in Zendesk Chat.