changing adapter for a new VPN

I recently signed up for a VPN, and when the installation was finished, the VP network now uses TAP-Windows Adapter V9. I want it to use my clearspot voyager, which is listed as "connect using" for a different LAN. The VPN won't access the internet unless the network assigned to my Clearspot (connect using: INFOMARK USB Ethernet/RNDIS Gadget #4) is connected, so when they are both connected, they both show up as connected, but the VPN won't connect otherwise. How do I change "connect using:" for the VPN so that it doesn't need the other network to connect? (so that it will connect itself straight to the mobile router)
Thanks!