Generative Fill now creating bizarre results

I used Generative Fill several times a few weeks ago with great results. I create a 1024 x 1024 selection and fill that, then move the selection square and create another fill, then repeat until I've extended the width of an entire image. It worked great. Now, however, even with simple fills, the results are bizarre.

In the example below, which is just a portion of the image, I'm trying to extend it to the left by 1014 pixels. I use a selection box of 1024 x 1024 pixels and overlap the image by 10 pixels. The main issue is that, while at the top of the selection square it created blue sky, it then generated a diagonal line with some green below it. There is no green anything like that in the full image. Then, below the green it's blank even though the selection is a square extending well below the area that it filled in. I have no idea what's going on. Anyone have a suggestion?

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