diff --git a/nullptr/mission.py b/nullptr/mission.py
index b4ff69a..9574ab2 100644
--- a/nullptr/mission.py
+++ b/nullptr/mission.py
@@ -188,7 +188,7 @@ class MiningMission(Mission):
     
   def step_sell(self, except_resource=True):
     target = self.st('resource')
-    market = self.store.get('Marketplace', self.ship.location())
+    market = self.store.get('Marketplace', self.ship.location_str)
     sellables = market.sellable_items(self.ship.cargo.keys())
     if target in sellables and except_resource:
       sellables.remove(target)