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[NARONGKORN KITRUNGROT]

I faced this problem after trying to deploy my first web app with app scripts, '
I get started with open Google sheet and extension and Google Scripts then 
direct to app scripts then change the filename and write this code 

function doGet(e) {

  return HtmlService.createTemplateFromFile('Index').evaluate();

}

then create Index.html file save it and

deploy it using web app configuration and Change Access Anyone I have tried opening with a test URL but the result is still the same