Hello @Shubham Jain , Thanks for using Microsoft Q&A Platform.
May I know the Azure resource region you are working on? I have reproduced the issue and found no issues.
Image captioning in Image Analysis 4.0 is only available in the following Azure data center regions: East US, France Central, Korea Central, North Europe, Southeast Asia, West Europe, West US, East Asia.
If you have to use a Vision resource outside these regions to generate image captions, please use Image Analysis 3.2 which is available in all Azure AI Vision regions.
You must use a Vision resource located in one of these regions to get results from Caption and Dense Captions features.
I hope this helps.
Regards,
Vasavi
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