Some PDF files will crash the PDF export function because of some characters they contain, but we cannot fix it because PDF files are generated using a PDF library from the system. You can try exporting another document to confirm that the PDF export function is working.
If possible, please export the document in GoodNotes document format and send to us to confirm that it is not a bug from GoodNotes.
You can recover the original PDF file by following these steps:
- Export the document in .goodnotes.zip format.
- Transfer the file to your computer.
- Unzip the file and the original PDF can be found inside the unzipped folder.