Actually, it's DR Congo for Democratic Republic of Congo. This is how it happened.
Around 1880, Europe, willy nilly pamby namby, cut up Africa into chunks of real estate recognizable on the map today as african countries. After distributing the land among themselves, a vast heavily forested land, criss-crossed by rivers and lakes, difficult to penetrate, was left, and awarded to the King of Belgium, Leopold. That land was known as Congo Free State.
As a kingly gesture, Leopold presented Congo to Belgians as a gift. Congo suffered unspeakable savagerie and exploitation at the hands of Belgians. Their cruelty was unrivaled anywhere in the world before, or since then. This left deep scars in the psyche of the country to this day. The country was renamed Belgian Congo.
At independence (1960), the name was changed to DR Congo. But soon after, Mobutu - a relic of Belgian colonization, and a product of the Cold War - emulated the colonialists by instituting a brutal and exploitive dictatorship. He renamed the country to Zaire. That name can be found in 15th century Portuguese maps of the region.
After Mobutu's overthrow, the name went back to what it was at independence: DR Congo. A rebirth, a new start, if you will.
So, jwenting, we know what the name is, at all times. It's just that our history can be too complex for people used to quiet lives to comprehend.