I have three teksavvy accounts and use vpns with all three of them.
A VPN basically passes your data over an encrypted tunnel over the public internet. Step 1 is to connect to the internet. Once you are connected then you establish the tunnel. Teksavvy does not block vpns (because I use them here) and your internet connection should not have anything to do with your vpn.
This sounds like a setup problem and not an ISP problem.