New Bot Channels Registration gets a 403 Forbidden while Testing the Web Chat from within Azure Portal

I have a Microsoft Bot Builder application hosted at the following URL

It is an App Service application, works fine when I connect emulators to it.

I decided to register a channel for it so I can talk to my bot using Web Chat so I went to Azure portal and created new Bot Channels Registration

Bot registration

I added the correct endpoint for my bot


When I talk to my bot using the Chat tester within Azure portal I get a Couldn't send error

couldnt send

Looking at the channel diagnosis I see I am getting 403 forbidden. My endpoint does not have an App ID or password, I don't need one for Emulator. What am I missing? 403