Azure AD B2C deployment fails with "The response for resource had empty or invalid content."

What could be the root cause of the following error message, when I try to deploy a fresh Azure B2C instance?

I receive the following error trying to deploy a fresh Azure B2C instance using BICEP.

{  
  "code": "DeploymentFailed",  
  "message": "At least one resource deployment operation failed. Please list deployment operations for details. Please see https://aka.ms/DeployOperations for usage details.",  
  "details": [  
    {  
      "code": "ResourceDeploymentFailure",  
      "message": "The response for resource had empty or invalid content."  
    }  
  ]  
}  

Creating a new instance in the Portal works fine. I receive the same error when I export the ARM template and try to deploy this via Azure CLI.

My BICEP file is

main.bicep

targetScope = 'resourceGroup'  
  
param location string  
  
module b2ctenant 'b2ctenant.bicep' = {  
  name: 'b2ctenant-module'  
  scope: resourceGroup()  
  params: {  
    location: location  
  }  
}  

b2ctenant.bicep

param location string  
  
resource b2ctenant 'Microsoft.AzureActiveDirectory/b2cDirectories@2021-04-01' = {  
  location: location  
  name: 'mattneugcontose01'  
  sku: {  
    name: 'Standard'  
    tier: 'A0'  
  }  
  tags: {}  
  properties: {  
    createTenantProperties: {  
      countryCode: 'US'  
      displayName: 'Contoso'  
    }  
  }  
}  

powershell deployment script:

$ResourceGroup = "rg-xxxxxxxx-xx-bicep-01"  
  
az account set --subscription "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"  
az group create --name $ResourceGroup --location eastus  
az deployment group create --resource-group $ResourceGroup --template-file main.bicep --parameters location=global  

Your help is appreciated.
Matthias