I'm assuming you want an evolution that needs "Indifferent" mood. Just to clear things up. Indifferent is this face:
Not to be confused with NEUTRAL, which is the default starting emotion.
If you're not doing that face at the time he evolves, then you won't get what you want. Also if you're using items to bump your digimon's level, special xp and whatnot, he might get a different emotion during this process.