Thank you for reaching out.
Thank you @Jackson Martins for the detailed troubleshooting above.
I think a support request will be required here to remove the subnet delegation and to delete the Virtual Network.
Could you please send an email to firstname.lastname@example.org with the details below so that I can enable a one-time free support ticket for you in this case.
Subject : Attn Chaitanya
Thread URL: Link to this thread.
Please let me know once you have done the same.
Hope this helps! Please let me know if you have any additional questions. Thank you!
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