Hello @Mahesh GADAGI , Thanks for using Microsoft Q&A Platform.
Could you please check the documentation once again and see whether VNet is configured accordingly. https://learn.microsoft.com/en-us/azure/cognitive-services/cognitive-services-virtual-networks?tabs=portal
If this is blocking you from creating the project; then I would suggest this temporary workaround to disable the VNet for the resource in order to create the project, and then enable it again to see if it helps.
Please try these and let us know.
I hope this helps.
Regards,
Vasavi
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