Hi Aleh Yablonski,
Please see if you have sufficient quota on GPU H100 SKU type. You can find quota details by below cli command. If you don't have sufficient quota, you can request for increase quota for H100 computes. If you have quota, check for other available regions by pass regional constraints. You find compute quota either through CLI command " az login --identity, az ml compute list-sizes -g <your RG name> -w <your AML workspace name> computelist.json" or Compute tab itself by clicking on "view my quota" as show in screenshot.
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I hope these helps you Thank you!