If she seems angry they're too young. You've paused them too much, or downloaded them. They have to be adults for 48 unpaused hours before they can use the dating channel. If you download them, the 48 hour timer starts over at 0.
If she's asleep, you've viewed it the maximum of three times per day that you're allowed to view it. (But you can trick it into thinking it's the next day by adjusting the clock so they go to sleep, then re-adjusting it so they wake up again.)