If you have connected the Apple Health app and Fitbit app within Asken Diet, you might be importing both step counts. We recommend that you open the Health app > Sources > Asken Diet and toggle off the Steps in the "Allow to Read Data" section at the bottom. This will stop the duplicate data import.
If you have connected to the Google Fit app and your Fitbit account you might be importing both step counts in to the Asken Diet app. We recommend you open the Asken Diet app > Side menu > Apps & Devices > Google Fit Settings and toggle off the "Steps data". This will stop the duplicate data import.