Complex sentence: Burgdorf again contacted Reymann, informing him that Hitler had personally appointed him to command the Berlin Defense Area, as a replacement to Bruno Ritter von Hauenschild-to prepare for the impending Battle of Berlin.
Split into simpler sentences: Burgdorf again contacted Reymann, informing him that Hitler had personally appointed him to command the Berlin Defense Area. Reymann was to replacement General Bruno Ritter von Hauenschild and to prepare for the impending Battle of Berlin.