Thank you for your message. I am sorry you are having this problem.
Are you trying to save the picture with a transparent background? You actually cannot do that from Firefly Generative Fill. However, you can take a Firefly generated image into Adobe Express and use that to make the image transparent.
Once in Adobe Express, open the image and you can select "Remove Background":
If you need to touch up what was made transparent, you can use the "Erase" feature to erase (make transparent) part of the image or restore (remove transparency) parts of the image.
I hope this helps. Let me know if you have any problems trying this out. If I misunderstood your issue, please let us know.