The 307-220 exchange is serviced by the following companies within the CHEYENNE ratecenter.
"T-MOBILE USA, INC."
Call are routed trough OCN 6529 and CLLI - CHYNWYFN1KD (Common Language Location Identifier Code) and Point of Interface (POI) switch which is located in CHEYENNE.
Who's number is 307-220 Numbers?