HomeGraph resourcemanager.projects.get permission on project error

[debugging]

I get this error pop up for a few seconds in the bottom of the screen  when using the homegraph tool

Error: The caller does not have permission 403:
Please make sure you have resourcemanager.projects.get permission on project ***** have granted all the permissions in the consent screen.

Any more information how to do this, I could not find this permission in the roles or IAM. 

Update: I Added  basic -> owner  permission to the IAM console for this project and now the error is :

Error getting Home Graph: No devices found for project id: xxxx

What does this mean ? Is this because of the account linking that did I also not could get working ?

[arm_dpe · Accepted solution]

Thanks for sharing. It seems you resolved the issue with permission.

For Error getting Home Graph: No devices found for project id: xxxx

This means that the Home Graph tool successfully authenticated and found your project, but it found no devices linked to your account within the scope of that project. For the Home Graph to have devices, the following two steps must have been completed successfully:

1. User Linking: A user must have successfully linked their Google account to your action through the Google Home app(via "Works with Google Home")

2. Device Syncing: Once the accounts are linked, your service must have successfully sent a SYNC response to Google, telling the Home Graph which devices the user owns.
   If the account linking failed, Google's Home Graph has no knowledge of any devices to report, leading to the "No devices found" error.

   
   We highly suggest to take a look at our Connect smart home devices to Google Assistant codelab. It will walk you through account linking, device sync, and Home Graph queries step by step. That should give you clarity on how roles, permissions, and linking all fit together.

[debugging]

The device linking issue was resolved , suddenly started working after a discussion with a google employee. Linking wss done and homegraph works now. Thanks.  The whole integation was working until a few  months ago incl. ReportState which is now the last part not working yet.