Depending on tutorial at microsoft website for IoT Hub if you type in second step:
az iot hub create --resource-group MyResourceGroup --name {YourIoTHubName}
in your cli, error comes up: *Invalid PartitionCount 4 - value must be between 2 and 2. If you contact a support representative please include this correlation identifier: ******-f9a8-4b36-a566-******, timestamp: 2019-06-04 14:32:30Z, errorcode: IH400016.*
See my answer below for fixing ;)