diff --git a/freqtrade/persistence/models.py b/freqtrade/persistence/models.py
index e8674007f..48f3cb676 100644
--- a/freqtrade/persistence/models.py
+++ b/freqtrade/persistence/models.py
@@ -324,7 +324,7 @@ class LocalTrade():
             'profit_pct': round(self.close_profit * 100, 2) if self.close_profit else None,
             'profit_abs': self.close_profit_abs,
 
-            'sell_reason': self.sell_reason + (f' ({self.buy_tag})' if self.buy_tag else ''),
+            'sell_reason': str(self.sell_reason) + (f' ({self.buy_tag})' if self.buy_tag else ''),
             'sell_order_status': self.sell_order_status,
             'stop_loss_abs': self.stop_loss,
             'stop_loss_ratio': self.stop_loss_pct if self.stop_loss_pct else None,