Complex sentence: The initial name proposed for the new town was Lucerne; however, the U.S. Post Office refused to accept the name because there already was a Lake Lucerne post office north of Miami in Dade County.
Split into simpler sentences: The initial name proposed for the new town was Lucerne. However, the U.S. Post Office refused to accept the name because there already was a Lake Lucerne post office north of Miami in Dade County.