Hi Yossef,
I'm Sumit, here to answer your query at the Microsoft Community.
26120 is the Beta channel Build.
Use the Beta Channel ISO file and try the upgrade, see Method 2 here:
https://www.yourwindowsguide.com/2024/07/instal...
https://www.microsoft.com/en-us/software-downlo...
Hope that helps, and rely on us for any further inquiries. All the best.
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