@Stephan Fopeano As far as I know Azure ML classic workspaces cannot be created after December 1st 2021, so is your web service or web service plan created prior to that?
If you have a classic workspace that is not used, try to delete that workspace if it is not in use. Navigate to https://studio.azureml.net/ and go to the settings tab to delete the workspace and its contents. You can also delete the webservices from the web services tab is required. I hope this helps!!
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