Foundry model deployment fails with 715-123420 for all tested models

We are blocked by backend model deployment failures in Azure AI Foundry with error code 715-123420.

Subscription: [SUBSCRIPTION ID REDACTED]

Tenant: [TENANT ID REDACTED]

Primary resource: [RESOURCE ID REDACTED]

Environment: ai-search-samples

Symptoms:

• ARM/Bicep validation fails with InvalidTemplateDeployment and inner code 715-123420.
• Direct CLI deployment creation also fails with 715-123420.
• Foundry account and project deploy successfully, but model deployment list remains empty.

Regions tested:

• swedencentral: failed
• eastus2: failed (validated with separate temporary AIServices account)

Models tested (all failing with 715-123420):

1. OpenAI text-embedding-3-large, version 1
2. Microsoft Phi-4, version 7
3. OpenAI gpt-5-chat, version 2025-10-03
4. Cohere Cohere-embed-v3-english, version 1
5. Cohere embed-v-4-0, version 1

Representative failing command pattern:

az cognitiveservices account deployment create --resource-group <rg> --name <account> --deployment-name <name> --model-format <format> --model-name <model> --model-version <version> --sku-name <sku> --sku-capacity <cap>

Observed response:

ERROR: (715-123420) An error occurred. Please reach out to support for additional assistance.

Recent tracking/correlation IDs:

• [REDACTED]
• [REDACTED]
• [REDACTED]

Request:

Please investigate and resolve subscription/tenant backend validation or entitlement issues preventing Azure AI Foundry model deployments for the listed models in these regions.