Delete a Task then Error: "Only members of the Microsoft 365 group are allowed to delete tasks."

Hello, I want to delete a task and get the following error message:
Only members of the Microsoft 365 group are allowed to delete tasks.Technical details Correlation
ID: c4794c1f-eade-4dc0-bd40-b8e37b93d1cf
Timestamp: 2024-08-14T11:29:39.521Z

We don't have a Microsoft 365 group  Does anyone have an idea?

Greetings from Germany