Issue found to be default gateway was mess up w/ wrong IP, once set back to router IP address then issue solve.
Such a dummy mistake..... very sorry guys....
Miss out to check the basic default gateway IP setting on DVR
Anyway, thanks for all your support and assist.
Wireless Help needed to setup CCTV DVR with WIFI Routers, MyCam380 DVR & DIR-615/1043ND/RT-N14UHP