Explanation:

You're creating a resource that will handle sentiment analysis (Language) and OCR (Vision) with a single key and endpoint. That is a Cognitive Services multi-service (Azure AI services) account.
When creating any Azure resource via ARM (HTTP/REST), the URL must be scoped to a subscription, not a tenant, and use the correct resource provider.
* Scope segment: Usehttps://management.azure.com/subscriptions/{subscriptionId}/resourceGroups/{rg}
/providers/...Therefore, choose subscriptions/8d3591aa-96b8-4737-ad09-00f9b1ed35ad (not the tenant scope).
* Resource provider: Multi-service cognitive account is under Microsoft.CognitiveServices.The full path to create would be like:/providers/Microsoft.CognitiveServices/accounts/{accountName}?api- version=2021-10-01 This creates a single Cognitive Services (Azure AI services) resource that provides one endpoint and one key across multiple services (e.g., Language for sentiment analysis and Vision for OCR).
* Azure Resource Manager: Create Cognitive Services account (Microsoft.CognitiveServices/accounts) using REST and API version 2021-10-01.
* Azure AI services (Cognitive Services) multi-service resource overview-single key/endpoint across services.