diff --git a/internal/rdb/rdb_test.go b/internal/rdb/rdb_test.go
index 235de12..1bfba53 100644
--- a/internal/rdb/rdb_test.go
+++ b/internal/rdb/rdb_test.go
@@ -3484,6 +3484,93 @@ func TestDeleteAggregationSet(t *testing.T) {
 	}
 }
 
+func TestDeleteAggregationSetError(t *testing.T) {
+	r := setup(t)
+	defer r.Close()
+
+	now := time.Now()
+	setID := uuid.NewString()
+	m1 := h.NewTaskMessageBuilder().SetQueue("default").SetGroup("mygroup").Build()
+	m2 := h.NewTaskMessageBuilder().SetQueue("default").SetGroup("mygroup").Build()
+	m3 := h.NewTaskMessageBuilder().SetQueue("default").SetGroup("mygroup").Build()
+	deadlineExceededCtx, cancel := context.WithDeadline(context.Background(), now.Add(-10*time.Second))
+	defer cancel()
+
+	tests := []struct {
+		desc string
+		// initial data
+		tasks              []*taskData
+		aggregationSets    map[string][]*redis.Z
+		allAggregationSets map[string][]*redis.Z
+
+		// args
+		ctx   context.Context
+		qname string
+		gname string
+		setID string
+
+		// expectations
+		wantAggregationSets    map[string][]redis.Z
+		wantAllAggregationSets map[string][]redis.Z
+	}{
+		{
+			desc: "with deadline exceeded context",
+			tasks: []*taskData{
+				{msg: m1, state: base.TaskStateAggregating},
+				{msg: m2, state: base.TaskStateAggregating},
+				{msg: m3, state: base.TaskStateAggregating},
+			},
+			aggregationSets: map[string][]*redis.Z{
+				base.AggregationSetKey("default", "mygroup", setID): {
+					{Member: m1.ID, Score: float64(now.Add(-5 * time.Minute).Unix())},
+					{Member: m2.ID, Score: float64(now.Add(-4 * time.Minute).Unix())},
+					{Member: m3.ID, Score: float64(now.Add(-3 * time.Minute).Unix())},
+				},
+			},
+			allAggregationSets: map[string][]*redis.Z{
+				base.AllAggregationSets("default"): {
+					{Member: base.AggregationSetKey("default", "mygroup", setID), Score: float64(now.Add(aggregationTimeout).Unix())},
+				},
+			},
+			ctx:   deadlineExceededCtx,
+			qname: "default",
+			gname: "mygroup",
+			setID: setID,
+			// want data unchanged.
+			wantAggregationSets: map[string][]redis.Z{
+				base.AggregationSetKey("default", "mygroup", setID): {
+					{Member: m1.ID, Score: float64(now.Add(-5 * time.Minute).Unix())},
+					{Member: m2.ID, Score: float64(now.Add(-4 * time.Minute).Unix())},
+					{Member: m3.ID, Score: float64(now.Add(-3 * time.Minute).Unix())},
+				},
+			},
+			// want data unchanged.
+			wantAllAggregationSets: map[string][]redis.Z{
+				base.AllAggregationSets("default"): {
+					{Member: base.AggregationSetKey("default", "mygroup", setID), Score: float64(now.Add(aggregationTimeout).Unix())},
+				},
+			},
+		},
+	}
+
+	for _, tc := range tests {
+		h.FlushDB(t, r.client)
+		t.Run(tc.desc, func(t *testing.T) {
+			SeedTasks(t, r.client, tc.tasks)
+			SeedZSets(t, r.client, tc.aggregationSets)
+			SeedZSets(t, r.client, tc.allAggregationSets)
+
+			if err := r.DeleteAggregationSet(tc.ctx, tc.qname, tc.gname, tc.setID); err == nil {
+				t.Fatal("DeleteAggregationSet returned nil, want non-nil error")
+			}
+
+			// Make sure zsets are unchanged.
+			AssertZSets(t, r.client, tc.wantAggregationSets)
+			AssertZSets(t, r.client, tc.wantAllAggregationSets)
+		})
+	}
+}
+
 func TestReclaimStaleAggregationSets(t *testing.T) {
 	r := setup(t)
 	defer r.Close()