Hello,
There are several ways to print barcode in SAP. Please see note 1557674.
1557674 - Overview of bar code printing from SAP system
1. Printing via bar code DIMM/SIMM or barcode-capable printer
2. Printing via a barcode.dll
3. New bar code technology
4. Using a bar code font
5. Printing via a PDF-based form
Please check by which way you printed the barcode.
Regards,
Yiming