Recently i have changed my ISP which provides its own Modem due to fiber optics (Broadband, TV and Phone in one line) now i have to use ISP modem. 

TP link Archer C9 (v1.0) provides me the Network HDD for media streaming on network.

Now i am facing problem when i am connected to ISP modem/wifi I am unable to access the HDD which is attached to Tp-link Archer C9.

Though I can stream internet without any difficulty on both router due to following setting at my router 

1. ISP modem IP scheme is set to 192.168.0.1
2. Tp-link Archer C9 IP Scheme is set 192.168.1.1 (with Dynamic IP mode for WAN)
3. I have connected the LAN connection from ISP modem to WAN port of Tp-link Archer C9

I have read the thread on different forum that to have access HDD from ISP modem I have to set the Archer C9 as AP (Access point) mode so that client connected to Tplink Archer C9 have same IP scheme and masking as of ISP modem

Tp-link Archer C9 V5.0 and above provides the option for operation mode as “Router” or “Access Point” in Admin webpage but I am using the V1.0

Please guide me how can make it work to have access the HDD (attached to Tplink Archer C9) from both router or how can I configure my Archer C9 as Access point