Complex sentence: For unknown reasons, on Frōzen Ghōst's second album their name changed from Frōzen Ghōst to Frozen Ghost, although on the third album the artist name returned to its original spelling of Frōzen Ghōst.
Split into simpler sentences: For unknown reasons, on Frōzen Ghōst's second album their name changed from Frōzen Ghōst to Frozen Ghost. Although on the third album the artist name returned to its original spelling of Frōzen Ghōst.