diff --git a/nullptr/api.py b/nullptr/api.py
index 1289ca5..c66a5d3 100644
--- a/nullptr/api.py
+++ b/nullptr/api.py
@@ -121,7 +121,7 @@ class Api:
       'tradeSymbol': typ.upper(),
       'units': units
     }
-    data = self.request('post', f'my/contracts/{contract}/deliver', data)
+    data = self.request('post', f'my/contracts/{contract.symbol.lower()}/deliver', data)
     if 'cargo' in data:
       ship.update(data)
     if 'contract' in data:
@@ -129,7 +129,7 @@ class Api:
     return contract
   
   def fulfill(self, contract):
-    data = self.request('post', f'my/contracts/{contract}/fulfill')
+    data = self.request('post', f'my/contracts/{contract.symbol.lower()}/fulfill')
     if 'contract' in data:
       contract.update(data['contract'])
     if 'agent' in data: