pixel_player_738928691 The Ptah's questline probably is not complete yet. You'll need to do that first before rusty talks.
See if you have any other yellow-frame quests in your quest tab.
If not, look for Ptah to talk to in his temple (somewhere among the ptah mines) or his Priest in town.
You can refer this guide on finding new quests with images: https://www.diggysguide.com/guides/finding-new-quests