Azure function running on consumption plan, not triggered by blob events

I have a azure function created with ARM Template by using powershell.

Function is blobtrigger type function running on **consumption plan**, to copy blob from source storage to destination storage.

When I upload blob to source storage it is not copied to destination. That means function is not executed.

When I browse function app through portal, function get invoked and do the required things as expected. Thereafter it works fine. It only happens when function app initially deployed by powershell script using ARM templates.

When I use App service plan instead of Consumption plan, everything works fine since function app is always running.

So I guess Issue is, when I create function app using ARM template and deployed using powershell it is in idle mode, and never triggered by blob events. Is my assumption correct or could you please help me to find the issue. Thanks