The game asked me to check on Olivia while she was using her phone in the living room, but there was no word 'new' during the check. I could only play games with her and couldn't advance her story.

It says that you have finished all the content for the update, so urs is probably bugged

idk if you’ve figured it out yet but you have to see her at night specifically when the girls are usually sleep in their room, she’ll be in the living room.

it won’t work if you see her during the day

In your case, try checking if all the criteria is fulfilled.

And then, some interactions are random. Try doing this a few times until it says you've completed that step

I just founded out the solutions. If you watch the TV with Emily in the living room, you can randomly choose the “pull her toward you”. Then Olivia will come down to the living room and say something about the TV show when you watch the TV. And later you can go to the living room when Olivia’s there. Then she will probably use her phone on the sofa. Sorry for bad English I’m foriegn hh good luck!