Good question!
The Bible actually refers to "Archangel" Michael, maybe in the book of Revelation, as the one who came down from heaven to cast out the devil, etc. A poor interpretation of what happened, as there are archangels, a separate being and we DO have an archangel circuit here on earth presently, but that one is our Creator Father Michael.
He did not use the same name as he was here on a different "mission":not as a Creator, but as one to live the life of his lowest will creature in the flesh.
Just as any man in your area is a father and is called "Father, Dad" by his children, and this same man has a name his community calls him, and as his parents might call him for "son", Michael, too, had different roles. Read Paper 119 to see the other 6 times he lived a different life to come closer to his creatures.