diff --git a/pkg/indicator/v2/boll.go b/pkg/indicator/v2/boll.go
index 9feda9f52..09335878d 100644
--- a/pkg/indicator/v2/boll.go
+++ b/pkg/indicator/v2/boll.go
@@ -58,4 +58,6 @@ func (s *BOLLStream) Calculate(v float64) float64 {
 
 func (s *BOLLStream) Truncate() {
 	s.Slice = generalTruncate(s.Slice)
+	s.UpBand.Slice = generalTruncate(s.UpBand.Slice)
+	s.DownBand.Slice = generalTruncate(s.DownBand.Slice)
 }