Workflow 2010 Find Interval Between Dates Problem

Hi all,
It's a simple situation. i want to find interval between two dates. For example interval between items start day and today. the result must be 24 but workflow calculate its as 2400!
The be more clarified: Start Day is created first as Date And Time filed and Display as Date and Time, and after that i changed as Date Only. And with powershell i updated the Start Day field's value as "8/11/2021 00:00:00 AM" . And the Today is a Worfklow variable that typed as Date/Time. And set it as Current Day.
Systems regional settings is set as Turkish date and time format "dd/mm/yyyy"
The output as below:
Today: 4.09.2021 00:00:00
Start Day: 11.08.2021 00:00:00
Interval: 2400
The workflow triggered with Information Management Policy every morning one a day.
The weird situation is if i started the workflow manual is calculated the interval correct. If workflow triggered with imp it calculates wrong.
it may be sound silly but i'm thinking to add some controls in workflow to check hundreds digit :(
Any help will be appreciated