Hi @Anonymous Thank you for posting your questions .
Which command are you using? Azure Cosmos DB supports automatic, server-side sharding. It manages shard creation, placement, and balancing automatically. Azure Cosmos DB does not support manual sharding commands, which means you don't have to invoke commands such as addShard, balancerStart, moveChunk etc. You only need to specify the shard key while creating the containers or querying the data.
Please see the supported cosmos DB's for MongoDB API Version 4.0