Thanks for asking question! Just to confirm in your Application Settings if you have any of the files sited here in the /home/site/wwwroot folder? If not, this could be a reason for this error. If so, recommend you go to your app service, under settings Click Configuration > Path mappings > You will see "Virtual applications and directories". Your virtual path should be "/" and physical path should be "site/wwwroot/" Change your Physical path to "site/wwwroot/'appname'" "appname" should be whatever the name of your application is. Or it should be whatever folder is inside of your "dist".
You may refer to this blog might be helpful.
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