My Wan ip in router shows 172.18.247.74
My public ip shows 111.125.207.xxx ( this comes in Dynu Ip update client and google->myip)

I can't ping my public ip my computer/ outside network.

I think i cant establish DDNS because my ISP has one more layer on top of my router ?
Is that correct ?

Any method to make this happen , please suggest.

After going through entire process of making username, installing client, port forwarding to my local pc from my router I still do not access to the domain name I registered.

Thanks and Regards,

Your ISP may be going through proxy. You can try using port 8245 to detect IP in the IP update client.