You need to progress with the main story.
Specifically the Eldritch leads.
If you somehow don’t have leads, check if you missed one of these steps:
- Note in the manor’s garden.
- Visit Gramps in the mountains.
- Do the 4 levels of martial training.
- Find the pigeon in the lake (check 3 times).
- Talk with Gramps again and now you should have the main story leads.