@Macit Giray GÖKIRMAK Thank you for reaching out to us on Microsoft Q&A forum!
As I understand from your post, you are trying to delete "dp-101" resource group, but the delete operation was not successful and even the resources are not available in the resource group. This seems like the delete operation was not successful or got stuck in the middle. To fix this issue, it needs to check by the technical support team from backend and take appropriate action. To reach out to Azure technical support team, you need to create a technical support ticket. The ticket enables you to work closely with the support engineers and get a quick resolution to your issue.
Here is the link - https://video2.skills-academy.com/en-us/azure/azure-portal/supportability/how-to-create-azure-support-request to create support case.
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