A paladin's charger needs a proper barding or it is little more than a mindless beast. The barding used by your charger not only needs to be of the finest materials possible, but must also be suitable for attunement to the spirit realm. There is a smith outside of Tarren Mill that has done great work for our paladins in the past. He is a modest and unassuming orc, but his work is superb and is well-suited to our needs. Seek him out and commission him for this task.