Thank you for posting your question in Microsoft Q&A.
Based on your description, I may have misunderstood your main point due to a possible translation error. Could you please confirm whether the delete function in Outlook is not working as expected? If yes, could you provide the information due to the following question to troubleshoot it effectively:
- Which Outlook version you are using? You can refer via: What version of Outlook do I have? - Microsoft Support
- Have you tried deleting it on another platform yet? If this issue occurred in the desktop app, you could try deleting it using the web app instead.
- Could you please confirm whether your account is a Business or Personal?
What mailbox are you unable to delete emails from? Are there any errors reported?
I will be waiting for your response. If you need further assistance, please let us know.