I'm building a chatbot for Facebook page using ExpressJs and Nodejs. I've tested my chatbot and it worked flawlessly with ngrok. My environment are:
- A server with static IP: 123.123.123.123, access internet via Draytek Vigor router with port 443 redirected.
- A sub domain: chatbot.abc.com with SSL pointed to my server IP (tested).
I can access the callback URL without any issue using the browser
But, Facebook keep saying that: "The callback URL or verify token couldn't be validated. Please verify the provided information or try again later." although I have checked the url and the verify token carefully.
I also using console.log(req.query) in the /webhook API to print out the query params if the API is called, it prints when I access the callback URL in the browser but when I tried with Facebook, there is nothing.
I've searched for a whole day but still found nothing useful, please help me, thanks!
