Model :

Hardware Version :

Firmware Version :

ISP :

I am having difficulties communicating between a wired device on a remote wired network to a device on the local wired network. My setup is as follows:
Archer C9 is the local router and AP 192.168.0.1/24
TL-WA801ND is the remote AP 192.168.0.254/24

192.168.0.18/24 is a Raspberry Pi on the remote network connected via wire (not wireless)
192.168.0.19/24 is a PCDUINO on the local wireless network
192.168.0.3/24 is a Synology NAS on the local wired network.

192.168.0.18 can communicate with (ping) all devices except 192.168.0.3 and vice versa.
192.168.0.19 can communicate with all devices including 192.168.0.3.

It seems that the remote network can not access the local wired network only. The remote network CAN access the Internet via 192.168.0.1 and can access the local wireless network.

I have tried the TL-WA801ND in Bridge, WDS Repeater, Universal Repeater and Client modes but all exhibit the same issues.

Any suggestions of what to try next?

Archer C9 4.1.0 Build 20160517 Rel. 35411 Hardware v1.0
TL-WA801ND 3.16.9 Build 150723 Rel.62240n Hardware v3

Thank you.