Hello @PENG XIA,
as long as the Azure Stream Analytics job runs, you will be charged for every unit you consume.
Cloud resources are consumed while the job is active.
You can stop the job for as long as you do not need it and restart it later on. See the restart options regarding the start time of the ingest:
You need to contact the Azure billing team to see if you are eligible for a refund. Please raise a support request to connect with an Azure billing support professional to help you with your concern.
Here is the link to create a support case.
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