This should be fixed in a patch soon (If it hasn't already gone out), but if the chibi was just sitting in your inventory when you logged off or restarted the game, when you come back it might look like 0 exp. re-equip the chibi and it should update, if the patch hasn't gone out though it's not just a visual glitch, don't try to earn alpha exp on an equipped chibi showing 0 xp if it should have more, re-equip it first. If the fix has already gone out, then it should just be a visual glitch that will only affect unequipped chibis.