Hello Geo García Downing,
Thanks for asking your query. Could you please check below steps
Review Data Loss Prevention Policy: Make sure your agent is following the most recent data loss prevention policies. At times, these policies may change and impact the functioning of your agent.Verify Environment and Compliance: Ensure your custom environment is correctly configured and all necessary security and compliance reviews are done. These are Security Assessment, Privacy review, Responsible AI assessment, and Accessibility.Check Agent Configuration: Ensure your agent is properly configured. Confirm the agent is allowlisted in PowerShield and that the custom connector policy is asked for and accepted.Update Manifest and App ID: In case you are faced with errors indicating that the app is already added, update the app ID and other details pertaining to your organization.Make sure that your agent's manifest file is properly set up and has no parsing errors. Look for Resource-Specific Consent (RSC) permissions where required. Debugging and Error Handling: Validate the manifest file for any errors and confirm proper application configuration. Debug the code and deploy it to the modern administrator account.
Incase,of any further query feel free to ask.Ref: https://microsoft.sharepoint.com/sites/SecuringAI/SitePages/Guidance--Working-with-Microsoft-Copilot-Studio-and-Copilot-Agents.aspx?web=1
https://learn.microsoft.com/en-us/microsoft-copilot-studio/error-codes?tabs=webApp
https://microsoft.sharepoint.com/sites/Microsoft365Builders/SitePages/Copilot-Studio-Custom-Agents.aspx?web=1
Thanks, Smita
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