I'm glad to hear that your issue has been resolved. And thanks for sharing the solution, which might be beneficial to other community members reading this thread. Since the Microsoft Q&A community has a policy that "The question author cannot accept their own answer. They can only accept answers by others ", I'll repost your solution in case you'd like to accept the answer.
Question: AzureML Data Labeling Project "Failed to submit one of the labels" when trying to convert a polygon to mask.
Answer: The workspace was not automatically using my own permissions to access the storage and the workspace itself didn't have the necessary permissions to access the storage either. After giving the workspace the necessary permissions, it worked.
If you encounter any issues in the future, don't hesitate to reach out to the community forum for assistance. Thank you.
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for was this answer helpful.