Java PDF Stamper writing below checkbox (text being covered by checkbox)

Im trying to write to an existing pdf using the java pdf stamper, but for some reason there is a certain checkbox in the pdf that the text appears to be drawn under.

Code for Reading pdf:

        PdfReader reader = new PdfReader(Testing.getImagePath() + "form.pdf");
        File dir = new File(Testing.getResourcePath() + id + "/");
        String destination = Testing.getResourcePath() + id + "form" + id + ".pdf";
        File exist = new File(destination);

        dir.mkdirs();
        PdfStamper stamper = new PdfStamper(reader, new FileOutputStream(destination));
        stamper.setFormFlattening(true);
        PdfContentByte over;
        over = stamper.getOverContent(1);

Code for Drawing text:

        over.beginText();
        over.setFontAndSize(bf, 11);
        over.setTextMatrix(169, 322);
        over.showText("X");
        over.endText();