The number should be in international format - +int area number.
The city where the company is headquartered. If adding a regional office or subsidiary pick the city where it is located.
1090 Vermont Avenue NW, Suite 700 Washington, DC 20005
Washington, D. C.
+20 2 2897800
+20 2 2891092
NCS V6 Includes New BIM Module, Symbols, Site/Civil Language