Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.
I understand that you are unable to delete your VNet because of a Service Association Link (SAL).
I suggested we create a service request for this and request our Engineer to delete the SAL from the backend.
Post which, you were able to delete the VNet successfully.
I hope we were able to resolve your issue and provide a timely solution.
Cheers,
Kapil.
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