@NamithaNarayanan-7003, Welcome to the Microsoft Q&A platform.
To create a data flow, select the plus sign under Factory Resources, and then select Data Flow.
This action takes you to the data flow canvas, where you can create your transformation logic. Select Add source to start configuring your source transformation.
For more information, see Source transformation.
Reference: Azure Data Factory – Data Flow
Incase, if you are not able to add the source; you may try the following steps and let us know.
- Clear “Cookies and Cached data” of your browser.
- Private Mode (New InPrivate Window).
- Try in different browser.
Hope this helps. Do let us know if you any further queries.
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