Supress data in a profitability analysis (COPA) planning

Good afternoon,

I have budgeted (KEPM) my sales planning and I want to supress some lines of my budget.

To do that, I underline the line I want eliminate and press the "delete" button. And I save.

But when I open an other time my budget I saw all the lines.

Do you know, how to eliminate definitly my budget's lines ?

Regards

Valérie