Language service is not working after RBAC implementation

Hi team,

We have implemented RBAC security for all the Azure resources we are using.

We have also updated the RBAC for the Language Service and AI Search.

For both services, we have enabled managed identity and assigned the appropriate RBAC role for the Language Service in AI Search. The setup works fine when the API key in Search is set to "API keys" or "both.", it fails when RBAC is selected in AI Search.

Even if the necessary permissions are added, we are encountering an "Azure Search Unauthorized" error while fetching answers from the Custom Question Answering project in the Language Service.

What could be the reason for this issue?