Config.system.sessions

2022-03-29T14:37:06.894+0000 I  SHARDING [Balancer] distributed lock 'config.system.sessions' acquired for 'Migrating chunk(s) in collection config.system.sessions', ts : 62424e2290d1f8de8d970b63
2022-03-29T14:37:06.903+0000 I  SHARDING [TransactionCoordinator] distributed lock with ts: '62424e2290d1f8de8d970b63' and _id: 'config.system.sessions' unlocked.
2022-03-29T14:37:06.906+0000 I  SHARDING [Balancer] Balancer move config.system.sessions: [{ _id: MinKey }, { _id: { id: UUID("00400000-0000-0000-0000-000000000000") } }), from shard2, to shard3 failed :: caused by :: InvalidOptions: cannot move chunks for a collection that doesn't exist
2022-03-29T14:37:06.906+0000 I  SHARDING [Balancer] about to log metadata event into actionlog: { _id: "ip-172-31-41-247.ap-northeast-2.compute.internal:27021-2022-03-29T14:37:06.906+0000-6243199290d1f8de8dd76693", server: "ip-172-31-41-247.ap-northeast-2.compute.internal:27021", shard: "config", clientAddr: "", time: new Date(1648564626906), what: "balancer.round", ns: "", details: { executionTimeMillis: 100, errorOccured: false, candidateChunks: 1, chunksMoved: 0 } }

I added a collection to a shard.
But the log is like this in the config server
It’s happening every second.
Why isn’t the collection created automatically?
Also, chunk migration is not happening because there is no collection.
What should I do?

version : 4.2.19

Did you add the collection directly to a shard or by connecting to the mongos? If you are working with a sharded cluster all connections should be to the mongos, it will route the traffic to the shard servers.