...
Open the Card Designer:
Go to the Configuration ribbon menu.
Open the Card Designer to edit your card layout.
Edit the Barcode Object:
Double-click the barcode object to open its properties.
Set the Format to String:
In the barcode properties, locate the Format drop-down option.
Change the format from Integer (or any other setting) to String. This step converts the numeric value into an alphanumeric value, which should retain the leading zero.
Using Variables and Script Object for Formatting
...