diff --git a/freqtrade/freqtradebot.py b/freqtrade/freqtradebot.py
index fce85baa3..5f2b72e1e 100644
--- a/freqtrade/freqtradebot.py
+++ b/freqtrade/freqtradebot.py
@@ -1021,12 +1021,12 @@ class FreqtradeBot(LoggingMixin):
 
         # Cancelled orders may have the status of 'canceled' or 'closed'
         if order['status'] not in constants.NON_OPEN_EXCHANGE_STATES:
-            filled_val = order.get('filled', 0.0) or 0.0
+            filled_val: float = order.get('filled', 0.0) or 0.0
             filled_stake = filled_val * trade.open_rate
             minstake = self.exchange.get_min_pair_stake_amount(
                 trade.pair, trade.open_rate, self.strategy.stoploss)
 
-            if filled_val > 0 and filled_stake < minstake:
+            if filled_val > 0 and minstake and filled_stake < minstake:
                 logger.warning(
                     f"Order {trade.open_order_id} for {trade.pair} not cancelled, "
                     f"as the filled amount of {filled_val} would result in an unsellable trade.")
diff --git a/freqtrade/persistence/models.py b/freqtrade/persistence/models.py
index 5f2db1050..b8ea5848f 100644
--- a/freqtrade/persistence/models.py
+++ b/freqtrade/persistence/models.py
@@ -799,11 +799,11 @@ class Trade(_DECL_BASE, LocalTrade):
     fee_close = Column(Float, nullable=False, default=0.0)
     fee_close_cost = Column(Float, nullable=True)
     fee_close_currency = Column(String(25), nullable=True)
-    open_rate = Column(Float)
+    open_rate: float = Column(Float)
     open_rate_requested = Column(Float)
     # open_trade_value - calculated via _calc_open_trade_value
     open_trade_value = Column(Float)
-    close_rate = Column(Float)
+    close_rate: Optional[float] = Column(Float)
     close_rate_requested = Column(Float)
     close_profit = Column(Float)
     close_profit_abs = Column(Float)