Hi,
Can you try with Powershell and see if you have same issue with the PS commands - https://learn.microsoft.com/en-us/powershell/module/az.resources/remove-azresource?view=azps-9.7.0
Also check the permissions as I can see it is greyed out the delete button - https://learn.microsoft.com/en-us/azure/azure-resource-manager/management/delete-resource-group?tabs=azure-powershell
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