Hello @j b ,
Thanks for your query , I just tried deploying f4sv2 in USWest2 Zone 1 which went through successfully. Probably it might be a temporary issue at that particular time.
Can you try to resize again ?
FYI - When you come across similar issue you can always try to resize to some other available SKU .
If the above information helps , kindly "Upvote and Accept the Answer"