Filename template in notify

Hi

I’m trying to create a notify where the file name is dependent on the year / month.
I use:

- platform: file
  name: notify_filename_test
  filename: /config/tmp/notify_test_{{now().strftime("%Y-%m")}}.csv
  timestamp: true   

but HA create a file with a completed diferent name.

What am I doing wrong?

I think it’s not possible to use templates for the filename.
Which file does HA create?

HA create a file named N6OXK8~E.CSV but this name is not always de same. When I resart HA on testing Automation and Notify the name changes but is always something like this.
Sem%20T%C3%ADtulo