To benefit the community/summarizing the comments discussion.
RichHolopoff-4511 was able to solve the issue by creating a new Azure App Service by clicking the "+Create a new app service" link in the Publish dialog in Visual Studio. Just quoting the comment - " The problem was totally my fault: I had ignored the "+" link in the Publish dialog thinking that I already had an app service from over six months ago."
To double-check if all the perquisites are installed/available for publishing to App Service via VS and also validate the deployment via Azure Portal.
Thanks for sharing an update on this with the community, @Rich Holopoff . Much appreciate your follow-up!
Additional info:
Reactivate a disabled Azure subscription
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