Using aspose.slides-15.2.0-jdk16.jar on Windows the attached pptx file is converted to the attached pdf file. As you can see the year 2011 appears as:
Thank you for considering Aspose.Slides.
I have observed your requirements and worked with the presentation file shared by you. I have been able to reproduce the issue. A ticket with ID SLIDESJAVA-34906 has been logged in our issue tracking system to further investigate and resolve the issue.This thread has been linked with the issue so that you may be automatically notified once the issue will be resolved.
We are sorry for your inconvenience,