Hmm, open walkthrough and look for her entire storyline it should be located in the middle and you will be able to see (orange color) how far you are in her storyline and roughly what you need to do to get there.
Hmm, please send your save to our e-mail or on our discord, we will take a look on it (alternatively enable cheats and in cheats menu press "start any talk" and then click on that one. (I still believe the conversation should be there among the options with no need to use cheats, but I better check it from your save)