@adscreen Thanks for asking question.
The error code 403 with subCode 10391
indicates that the user is not authorized to perform the operation. This error can occur if the user does not have the required permissions to access the call queue.
To resolve this issue, you can check the following:
Ensure that the user has the required permissions to access the call queue. You can check the permissions by going to the Azure portal and navigating to the call queue resource. Then, click on the "Access control (IAM)" tab and verify that the user has the required role assigned.
Check if the Communication Services token used to establish the call is valid and not expired. You can generate a new token and try again.
Ensure that the number you're calling (or call you're joining) exists.
See- Troubleshooting in Azure Communication Services
Please let us know if issue remains, happy to assist further.