Screen recorder with Huawei P30?

I noticed that I do not start screen capture by tapping my knuckles on the display twice, despite the activation of this setting.

But synonymous with switch the screen recorder is not displayed.

I do not want to download any extra app.

Do you have any idea why this did not work?

Did I do something wrong?

Press the sound key and the power key at the same time

Does not work either

Then you have to download a recorder.