diff --git a/pkg/utilsv2/demo.go b/pkg/utilsv2/demo.go
new file mode 100644
index 000000000..0979d390e
--- /dev/null
+++ b/pkg/utilsv2/demo.go
@@ -0,0 +1,13 @@
+package utilsv2
+
+import "Open_IM/pkg/common/db/table"
+
+func demo() {
+
+	groups := []*table.GroupModel{}
+
+	groups = DuplicateRemovalAny(groups, func(t *table.GroupModel) string {
+		return t.GroupID
+	})
+
+}
diff --git a/pkg/utilsv2/slice.go b/pkg/utilsv2/slice.go
index 4d1dca3ac..96245a276 100644
--- a/pkg/utilsv2/slice.go
+++ b/pkg/utilsv2/slice.go
@@ -1,23 +1,10 @@
 package utilsv2
 
-import "Open_IM/pkg/common/db/table"
-
-//func DuplicateRemoval[T comparable](ts []T) []T {
-//	v := make([]T, 0, len(ts))
-//	tmp := map[T]struct{}{}
-//	for _, t := range ts {
-//		if _, ok := tmp[t]; !ok {
-//			tmp[t] = struct{}{}
-//			v = append(v, t)
-//		}
-//	}
-//	return v
-//}
-
 func DuplicateRemovalAny[T any, V comparable](ts []T, fn func(t T) V) []T {
 	v := make([]T, 0, len(ts))
 	tmp := map[V]struct{}{}
-	for _, t := range ts {
+	for i := 0; i < len(ts); i++ {
+		t := ts[i]
 		k := fn(t)
 		if _, ok := tmp[k]; !ok {
 			tmp[k] = struct{}{}
@@ -33,16 +20,6 @@ func DuplicateRemoval[T comparable](ts []T) []T {
 	})
 }
 
-func demo() {
-
-	groups := []*table.GroupModel{}
-
-	groups = DuplicateRemovalAny(groups, func(t *table.GroupModel) string {
-		return t.GroupID
-	})
-
-}
-
 func DeleteAt[T any](ts []T, index ...int) []T {
 	switch len(index) {
 	case 0:
@@ -54,10 +31,12 @@ func DeleteAt[T any](ts []T, index ...int) []T {
 		for _, v := range index {
 			tmp[v] = struct{}{}
 		}
-		for i, t := range ts {
-
+		v := make([]T, 0, len(ts))
+		for i := 0; i < len(ts); i++ {
+			if _, ok := tmp[i]; !ok {
+				v = append(v, ts[i])
+			}
 		}
-
+		return v
 	}
-	return nil
 }