I have an issue with Amy as well (I searched before posting) I have it where I caught her and Tai but failed to get the event at night with her and Tai and now she doesn't ever show up doing anything bad, my discipline level is 150 so I doubt she'll show up again meaning I can't train Potts, meaning I can't get the rest of Mary and Louise content either. Also means getting 12 influence, meaning I can't do Maxine Charity event.
Shouldn't need Amy to do anything at (lol) 150.
We all want Tia added to the character roster.
Have had something like this happen very early in the game, where Amy runs into MC in the hall, MC teaches an afternoon class, Cassandra misbehaves, and Amy's level doesn't increase after punishment, so even though quest updates, you need to get run over in the hall again to advance.