I'm having the same problem. I chose license and save to my library but the Adobe watermark is still on the photos. This has happened to me many times and half of my images in my library still have your watermark. It's frustrating. Please help.
As you have mentioned that half of your images have watermark so the issue might be that you might be downloading the preview of the images rather than using the license version, in that case the image still shows the watermark. I would advise you to go through the following link for more details
Please feel free to update this thread in case of any additional query.