Sixth Panzer Army commander SS-Oberstgruppenführer Sepp Dietrich ordered Hermann Prieß , commanding officer of the I SS Panzer Corps , to increase its efforts to back Peiper 's Kampfgruppe , but Prieß was unable to break through .
Sixth Panzer Army commander SS-Oberstgruppenführer Sepp Dietrich ordered Hermann Prieß , commanding officer of the I SS Panzer Corps , to help Peiper 's Kampfgruppe , but Prieß was unable to break through .