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The subscription is not allowed to create or update the serverfarm
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Portal Fails to create Web App Service - Bad Gateway
Attempted to create Web App Resource using windows .Net 8, initially on "try for free for 12 months" plan, then on pay-as-you-go plan. After working through wizard and clicking create, the portal starts trying to create the Windows Plan (I have tried with Free F1, Basic B1, and Standard S1 pricing plans), whereupon it reports a "Bad Gateway" error. The detailed JSON report states, "The subscription xxx is not allowed to create or update the server farm." with a code "Forbidden".