Hi @me-subhasis ,
Welcome to Microsoft Q&A platform and thanks using this forum.
I just tried creating a Stream Analytics job in West US 2 region without any issues.
This could be an intermittent issue. Could you please clear your browser's cache, restart browser and try again to check if you are experiencing the same behavior?
In addition to above, please make sure Microsoft.StreamAnalytics Resource provider is registered with your subscription.
If you still experience the issue consistently, please let us know what is the location/region you are using to create your Stream Analytics job?
Let us know how it goes.
Looking forward to your confirmation.
Thank you
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