You are looking too far in.
In the General Tab of your char, where is lists the name, sex, and level, there is a drop down saying "last difficulty completed" just select adventure, and make sure you change his quests to all completed.
In the General Tab of your char, where is lists the name, sex, and level, there is a drop down saying "last difficulty completed" just select adventure, and make sure you change his quests to all completed.