Based on the documentation https://learn.microsoft.com/en-us/rest/api/iothub/service/modules/invoke-method it seems the api_version parameter needs to be specified when invoking a direct method in an edge module. Where can I find this api_version parameter to specify in the URL? I looked in the device and module twins and cannot seem to find this parameter anywhere.
The api_version is currently the same for all IoT Hub API calls and is 2018-06-30.
This is documented here https://learn.microsoft.com/rest/api/iothub/