Eventhub Capture puts files in the wrong place

Question

I have an eventhub with capture to data lake enabled. File pattern is:

data lake path: /

mydata/{Namespace}-{EventHub}-{PartitionId}/{Year}-{Month}-{Day}/{Hour}-{Minute}-{Second}

e.g mydata/mydatahubs-mydatahub-0/2018-3-12/11-54-14

It puts data to:

mydata/mydatahubs-mydatahub-0/2018-04-12/01-53-54.avro.temp/0022f0cf-5b8f-4dc1-ab08-a8cc1b55399b

It is supposed to create *.avro files. Why is it happening? What is this .avro.temp?