diff --git a/blankly/data/data_reader.py b/blankly/data/data_reader.py
index 45c11b77..c9d1e139 100644
--- a/blankly/data/data_reader.py
+++ b/blankly/data/data_reader.py
@@ -111,7 +111,7 @@ def _parse_df_prices(self, file_paths: list, symbols: list, columns: set) -> Non
             self._check_length(file_paths[index], file_paths[index])
 
             # Check if its contained
-            assert (columns.issubset(file_paths[index].columns))
+            assert (columns.issubset(file_paths[index].columns)), f"{columns} not subset of {file_paths[index].columns}"
 
             # Now push it directly into the dataset and sort by time
             self._internal_dataset[symbols[index]] = file_paths[index].sort_values('time')
@@ -130,7 +130,7 @@ def _parse_csv_prices(self, file_paths: list, symbols: list, columns: set) -> No
             self._check_length(contents, file_paths[index])
 
             # Check if its contained
-            assert (columns.issubset(contents.columns))
+            assert (columns.issubset(contents.columns)), f"{columns} not subset of {contents.columns}"
 
             # Now push it directly into the dataset and sort by time
             self._internal_dataset[symbols[index]] = contents.sort_values('time')
diff --git a/blankly/exchanges/interfaces/paper_trade/paper_trade_interface.py b/blankly/exchanges/interfaces/paper_trade/paper_trade_interface.py
index 640a64ec..1575bfc5 100644
--- a/blankly/exchanges/interfaces/paper_trade/paper_trade_interface.py
+++ b/blankly/exchanges/interfaces/paper_trade/paper_trade_interface.py
@@ -352,10 +352,10 @@ def get_account(self, symbol=None) -> utils.AttributeDict:
                 return self.local_account.get_account(symbol)
             except KeyError:
                 if self.backtesting:
-                    raise KeyError("Symbol not found. This can be caused by an invalid quote currency "
+                    raise KeyError(f"Symbol {symbol} not found. This can be caused by an invalid quote currency "
                                    "in backtest.json.")
                 else:
-                    raise KeyError("Symbol not found.")
+                    raise KeyError(f"Symbol {symbol} not found.")
 
     def take_profit_order(self, symbol: str, price: float, size: float) -> TakeProfitOrder:
         # we don't simulate partial fills, this is the same as take_profit