Using multiple consumers with CosmosDB change feed

I am trying to use cosmos db change feed (I'm referring to https://docs.microsoft.com/en-us/azure/cosmos-db/change-feed-processor and https://github.com/Azure/azure-cosmos-dotnet-v2/tree/master/samples/code-samples/ChangeFeedProcessorV2).

When I start a multiple instances of a consumer, the observer seems to see only 1 partition key range. I only see a message - Observer opened for partition Key Range 0 and it starts receiving the change feed. So, the feed is received by only 1 consumer at any given point. If I close one consumer, the next one picks up happily.

I can't seem to understand the partition keys / ranges in cosmos db. In cosmos db, I've created a database and a collection within it. I've defined a partition key - /myId. I store a unique guid in myId. I've saved about 10000 transactions in the collection.

When I look at partition key ranges using api (/dbs/db-name/colls/coll-name/pkranges), I see only node under PartitionKeyRanges. Below is the output I see

{
    "_rid": "LEAgAL7tmKM=",
    "PartitionKeyRanges": [
        {
            "_rid": "LEAgAL7tmKMCAAAAAAAAUA==",
            "id": "0",
            "_etag": "\"00007d00-0000-0000-0000-5c3645e70000\"",
            "minInclusive": "",
            "maxExclusive": "FF",
            "ridPrefix": 0,
            "_self": "dbs/LAEgAA==/colls/LEAgAL7tmKM=/pkranges/LEAgAL7tmKMCAAAAAAAAUA==/",
            "throughputFraction": 1,
            "status": "online",
            "parents": [],
            "_ts": 1547060711
        }
    ],
    "_count": 1
}

Shouldn't this show more partition key ranges? Is this behavior expected?

How do I get multiple consumers to receive data as shown under https://docs.microsoft.com/en-us/azure/cosmos-db/change-feed-processor?