Why do I get the error Failed to add team member. Please try again. when trying to add an agent to the chat group?
The agent does not have Chat enabled in agent permissions within their profile. To fix the issue, make sure you enable Chat for the agent in Admin Center.
For steps on updating agent permissions in Chat, see the article: Setting roles and access in Zendesk Admin Center.
For enabling chat roles in Legacy Chat accounts, see the article: Chat is not enabled for you.