Ionic PSPDFKit how to save annotations

Hello
I am developing an application with ionic and I would like the user to be able to open a pdf (i use PSPDFKit plugin) and make the annotations there.
for the moment, I can open the pdf and make the annotations, but these annotations are not saved when we close the file, despite the fact that I activate the automatic saving in the options of opening my file.

here is my code


    options =  {  autosaveEnabled: true, 
                  annotationEditing: {
                  enabled: true, 
                  creatorName: 'Mr Kaplan'
                },
              };

      this.platform.ready().then(() => {
         const DOCUMENT = this.platform.is("ios")
         ? "Document.pdf"
         : "file:///android_asset/Document.pdf";
        PSPDFKit.present(DOCUMENT,this.options);
    });

please how to save these annotations