Ok, I think I can see the full picture now. Here's what you need to do:
- Set "Local IP address/Subnet mask" like this:
- Set "Remote IP address/Subnet mask" like this:
Also, the IP 10.142.13.9 looks like it was set up manually (static IP). Is this true or was the IP assigned via DHCP? If it was assigned with DHCP, then all should work fine. If it's a static IP you may need to add this firewall rule in the router's Network → Firewall → Custom Rules page:
iptables -I FORWARD -s 10.142.13.9/32 -j ACCEPT