Calculate duration between 2 dates

I want to enter 2 dates (“date 1” and today()) and the FEEL expression should calculate how many days lie between them. I have tried the following expression, but unfortunately it doesn’t work:

days and time duration(date(date1), today()).days

Input:

{
  "date1": "2022-12-22T13:13:21.895"
}

Where are you testing this?