Record application file lost after hangup


To record audio from a caller I have this in extensions.conf (Asterisk 13.1-cert2):

I see that a wave file got created and the size is increasing. But after the caller hang up the wave will be removed. If I use something like this:

And a caller talks for at least 20s the audio will not be removed.

From my point of view this can’t be a permission problem. I played with the ‘h’ extension:

But the file is already removed at this step.
How can I achieve that the audio file will never be removed?