Delete an already released transport request

Hello together,

I have a problem in SE09/SE10 with a transport request.

The request is as follows:

Modifiable

D01K939667 100 Username /Description

D01K939668 Username Customizing Task

The requests itself has the status "Modifiable". The task D01K939668 within the request is already released. I have to delete the whole request now, but when trying to delete it, it says "Request D01K939668 already released". How can I delete a task within a request, that is already released?

Thank you for any help!

Best regards

Klaus Hirschegger