Hello @matteor19112684,
Thank you for your message. I am sorry you are having this problem.
Do you mean the "Upscale" button:

The upscale button is only supposed to be displayed when you have generated a fastmode image (generally 500x500). If you did not have fastmode on, you already have an upscaled image and cannot upscale further in Firefly.

If you had Fast Mode on, and the upscale button is not present, please post a photo of the browser window and tell us what OS and browser you a
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