Apache POI Merge Multiple Decks to Single Deck

I'm using Apache POI - 5.2.2 to load the decks as ByteArrayInputStream. These loaded decks to be merged to a single large deck. I'm following mentioned steps -

1. Download the file as ByteArrayOutputStream
2. Convert the downloaded file to InputStream
3. Load the deck in Apache POI

   XMLSlideShow slideShow = new XMLSlideShow(stream);

4. Iterating over each slide from the loaded deck

   slideShow.getSlides();

5. Create a new slide in the Target Deck

   targetDeck.createSlide()

   // Another method is available but doesn't work for the layouts

   targetDeck.createSlide(srcSlide.getSlideLayout); //

6. Tried importing content and layout from srcSlide to targetDeck Slide

        XSLFSlide newSlide = targetDeck.createSlide(srcSlide.getSlideLayout());
        // copy source layout to the new layout
        newSlide.getSlideMaster().importContent(srcSlide.getSlideMaster());
        newSlide.getSlideLayout().importContent(srcSlide.getSlideLayout());
        newSlide.importContent(srcSlide);

After all mentioned steps, when I try to output the targetDeck as stream, it doesn't retain any source layouts.

Reference