If you had bothered to do what I told you last time you posted this question:
Load a image from URL to picture box using c#.net[
^] you would have seen what was going on: it's a PNG image. And a quick test with your code shows it works. Except ... you didn't read the documentation:
Image.FromStream Method (System.Drawing) | Microsoft Docs[
^] which clearly states:
Remarks
You must keep the stream open for the lifetime of the Image.
You don't. You specifically Dispose the stream once you have created the Bitmap, which means the image is no longer valid.
Go back to your existing code, create Bitmap object, use the debugger to prove it is correct - as I suggested yesterday - and then copy the image to a new bitmap before you Dispose the Stream.
A quick check with the debugger would have shown you that the image was valid inside the
using
block and invalid outside it a day ago ... so why didn't you try using it?