Cannot get the app COOKIE

I have got a test app deployed v25 now but still cannot cat app/releases/COOKIE, file not found.

I fly secrets set RELEASE_COOKIE=[ value] and it bump up a version.

I did fly secrets list and the release COOKIE was listed

I did cat app/releases/COOKIE, file not found

I even added a releases function in the Release module with the cookie generated.

Thank you.