Since this is windows you might need to wrap the -F URL in "
.\twitch.exe event verify-subscription follow -F "https://myngrokurl/webhooks/callback/" -s rString
I don’t have it installed on my windows machine as I’m mac based.
And/or if it is hitting your callback you can debug whats going on in your code.
Grabbed it on Windows.
Looks like your callback is not working as expected, since it got a unexpected EOF when calling your callback, that was the response from your server