If you are using the same subnet on both ends you results would be totally unpredictable. Make sure that each remote network has their IP network. That will correct your network connectivity issue.
Now if you are determined to use the same network on each end you would have to break that original subnet into pieces.
Example: 4 subnets(4 networks of 64 addresses)
That would be a subnet mask of 255.255.255.240(28 bit mask).
I have 7 VPN tunnels running from behind my PF-Sense each has there on unique 255.255.255.0(24 bit mask). I even have IPsec VPN tunnels for remote VPN connectivity and OpenVPN connectivity. Each one of those has their on unique subnet.
So in all my small home/business network has 7 active vpn tunnels, 5 internal subnets(business network, storage network(ISCSI), wireless subnet, IPsec VPN tunnels, OpenVPN tunnels) I am actively using 5 class C (24 bit subnets) and accessing 7 class networks (24 bit networks)
I work very hard to implement as much technology in my home/business network that keeps my network and infrastructure skill strong. I have gone totally virtual as well no real servers in my farm. I am using XenServer Enterprise, with OpenFiler (ISCSI target service enable, SMB service enable, and NFS). So that in a nut shell is what I am doing with my home network.
RC
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