I have an Azure Function in Net 4.8 (stuck to framework due to WCF)

The Function is trying to receive messages from Azure Servicebus using ServiceBusTrigger.

I get en exception stating:

Cannot convert input parameter 'message' to type 'Azure.Messaging.ServiceBus.ServiceBusReceivedMessage' from type 'System.String'

My assumption is that my function is running “in-process” instead of “isolated” since it tries to map the first argument as a string instead of ServiceBusReceivedMessage, is this correct?

But I can’t understand why it is running in-process then.

In my .csproj I have “Exe”

<TargetFramework>net48</TargetFramework>
<AzureFunctionsVersion>v4</AzureFunctionsVersion>
<OutputType>Exe</OutputType>

I’m referencing the following packages:

    <PackageReference Include="Azure.Messaging.ServiceBus" Version="7.17.5" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.ServiceBus" Version="5.18.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Extensions.Timer" Version="4.0.1" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker" Version="1.10.0" />
    <PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="1.7.0" />

My host.json has:

{
   "version": "2.0"
}

My deployed function has the following app settings:

{
    "name": "FUNCTIONS_EXTENSION_VERSION",
    "value": "~4",
    "slotSetting": false
  },
  {
    "name": "FUNCTIONS_WORKER_RUNTIME",
    "value": "dotnet-isolated",
    "slotSetting": false
  }

My implementation is decorated with:

[Function("myspecialfunction")]
public async Task Run([ServiceBusTrigger("myspecialqueue", Connection = "<secret>")] ServiceBusReceivedMessage message, ServiceBusMessageActions messageActions)

What could possibly be wrong?