@jai25 Unfortunately, the problem is not reproducible. We have used the following code for testing:
Document doc = new Document();
DocumentBuilder builder = new DocumentBuilder(doc);
InputStream ins = new ByteArrayInputStream(Files.readAllBytes(Paths.get("C:\\Temp\\OleObject.pdf")));
builder.insertOleObject(ins, "AcroExch.Document.7", true, null);
doc.save("C:\\Temp\\out.docx");
@jai25 The problem is not reproducible using 16.11 version of Aspose.Words for Java. Here is the output document produced by 16.11 version on my side: out.docx (5.1 MB)