Thanks everyone,
By following Rafeeq and Vikram Kumar solutions, I have discovered the ICMP Ping, Pong are not covering all service so I went in and check all service id numbers.
The numbers are below for me to try disable ping under ICMP:
0,3,4,5,6,8,9,10,11,12,13,14,15,16,17,18,30,31,32,33,34,35,36,37,38,39,40
Now it works, but i am not really sure if it really requires that much to block under ICMP service that used to stop ping.
Regards,
Eric Chan