Can't connect via VPN from one building block to another?

Question

VPN

I can’t connect via VPN from one building to another (the buildings are located in different parts of the city) and both buildings have the same white ip (there is one provider), the connection goes through from the other Internet. What is the solution?

Answer 1

and both cases have the same white ip

Hm. What does this mean?

Answer 2

Do not use an external white ip to connect the VPN, but use the internal one if you are inside the same local network with another case.