Carrier Issue

Hello all ,
I have a Vicidial set up,we tried to use a carrier who said that their IP is a local one and cannot be connected to a public IP which is required for SIP calls ,can anyone please suggest a solution to allow us make and receive outbound calls..
I have a Vicidial set up,we tried to use a carrier who said that their IP is a local one and cannot be connected to a public IP which is required for SIP calls ,can anyone please suggest a solution to allow us make and receive outbound calls..