diff --git a/pkg/strategy/xgap/strategy.go b/pkg/strategy/xgap/strategy.go
index 209fb3126..4bd18dfbe 100644
--- a/pkg/strategy/xgap/strategy.go
+++ b/pkg/strategy/xgap/strategy.go
@@ -132,17 +132,17 @@ func (s *Strategy) CrossRun(ctx context.Context, _ bbgo.OrderExecutionRouter, se
 	}
 	s.sourceSession = sourceSession
 
+	s.sourceMarket, ok = s.sourceSession.Market(s.SourceSymbol)
+	if !ok {
+		return fmt.Errorf("source session market %s is not defined", s.Symbol)
+	}
+
 	tradingSession, ok := sessions[s.TradingExchange]
 	if !ok {
 		return fmt.Errorf("trading session %s is not defined", s.TradingExchange)
 	}
 	s.tradingSession = tradingSession
 
-	s.sourceMarket, ok = s.sourceSession.Market(s.SourceSymbol)
-	if !ok {
-		return fmt.Errorf("source session market %s is not defined", s.Symbol)
-	}
-
 	s.tradingMarket, ok = s.tradingSession.Market(s.Symbol)
 	if !ok {
 		return fmt.Errorf("trading session market %s is not defined", s.Symbol)