Message enrichments Not for Free tier ??

I am using the free tier of IoT hub, and I am having trouble using Message Enrichment.

when I try to use $twin.tags.Location, value, it stores the string "$twin.tags.Location" instead of actual value.
Yes, the Exact tag value is there in the device twin. 

according to this https://docs.microsoft.com/en-gb/azure/iot-hub/iot-hub-message-enrichments-overview#applying-enrichments,

1. this error will occur in the basic tier.
   • but I am using a free tier. and according to this https://azure.microsoft.com/en-in/pricing/details/iot-hub/, Free tier is part of the standard tier. 
     
   • And it is mentioned nowhere that this feature is not available in the free tier.
2. The error will occur if the tag value is not present in the device twin.
   • but value is there. 

Is something I am missing here ???