AI-3019 - Explore the Azure AI Extension - Bicep Deployment Issue

AI-3019 - Lab 01 (CSS-r): Explore the Azure AI Extension
Task: Deploy resources into your Azure subscription
Step 7: Finally, use the Azure CLI to execute a Bicep deployment script to provision Azure resources in your resource group:

az deployment group create --resource-group $RG_NAME --template-file "mslearn-postgresql/Allfiles/Labs/Shared/deploy.bicep" --parameters restore=false adminLogin=pgAdmin adminLoginPassword=$ADMIN_PASSWORD

When running this code, it fails with "CustomDomainInUse". I have tried this with multiple sets of credentials from the same cloud sub pool, and found no existing artifacts in any of the subscriptions that should cause this.