Zend certified PHP/Magento developer

Port forwarding not working only for devices connected on same wifi

So I have a .NET server running on my desktop. https://192.168.0.xxx:7089/WeatherForecast

192.168.0.xxx is also my ipv4 address.

Now, I am trying to access this from outside world. I barely know anything about networking but I know that 192 is private IP address and therefore it’s not exposed to the internet.
So now the question is how do I access it from outside?

This is how I have configured port forwarding. The IP which is hidden is my dynamic IPv4 of my computer where the webserver is running.

port forwarding configuration

I tried to access https://192.168.0.xxx:8181/WeatherForecast from outside but I couldn’t.

So I tried IP of my router 100.71.xx.xx and it worked! I was able to hit the API from another device(smart phone) at home which is on the same wifi. But as soon as I turn the wifi off and switch to cellular data, it stops working.

I just did a quick what’s my IP and found and IP that starts with 1.186.xxx…. and tried that. It didn’t work either. :/