Well, 7 pm might be too late for this time of the year. My birds are getting dinner at 4:45 pm and they are already all asleep before 8 pm. You can't really go by the amount of light outdoors when it comes to the solar schedule because the days are always 'shorter' indoors.
And, no, there is no such thing as a forever unpredictable bird. Even abused ones and wild-caughts become even-tempered if treated right for a long time. Just be patient and stick to the right husbandry and you'll see.