diff --git a/src/fiber/graph.rs b/src/fiber/graph.rs
index 38621a96..edd96bb5 100644
--- a/src/fiber/graph.rs
+++ b/src/fiber/graph.rs
@@ -609,11 +609,19 @@ where
     ) -> Result<Vec<PathEdge>, GraphError> {
         let started_time = std::time::Instant::now();
         let nodes_len = self.nodes.len();
+        let route_to_self = source == target;
+
         let mut result = vec![];
         let mut nodes_visited = 0;
         let mut edges_expanded = 0;
         let mut nodes_heap = NodeHeap::new(nodes_len);
         let mut distances = HashMap::<Pubkey, NodeHeapElement>::new();
+        // a map from node_id to the selected channel outpoint
+        // suppose the scenario of A <-- channel_1 --> B <-- channel_2 --> A
+        // when we starting iterate channels from A, we may considerting channel_1 and channel_2,
+        // and we selected channel_1 according to weight
+        // in this case, `last_hop_channels` stores (B -> channel_1) so that we can skip channel_1 when we iterate channels from B
+        let mut last_hop_channels = HashMap::new();
 
         if amount == 0 {
             return Err(GraphError::Amount(
@@ -651,8 +659,7 @@ where
             next_hop: None,
             incoming_htlc_expiry: 0,
         });
-        let route_to_self = source == target;
-        let mut last_hop_channels = HashMap::new();
+
         while let Some(cur_hop) = nodes_heap.pop() {
             nodes_visited += 1;
 
@@ -682,11 +689,6 @@ where
                 // if the amount to send is greater than the amount we have, skip this edge
                 if let Some(max_fee_amount) = max_fee_amount {
                     if amount_to_send > amount + max_fee_amount {
-                        debug!(
-                            "amount_to_send: {:?} is greater than sum_amount sum_amount: {:?}",
-                            amount_to_send,
-                            amount + max_fee_amount
-                        );
                         continue;
                     }
                 }
@@ -696,19 +698,9 @@ where
                     || (channel_update.htlc_maximum_value != 0
                         && amount_to_send > channel_update.htlc_maximum_value)
                 {
-                    debug!(
-                        "amount_to_send is greater than channel capacity: {:?} capacity: {:?}, htlc_max_value: {:?}",
-                        amount_to_send,
-                        channel_info.capacity(),
-                        channel_update.htlc_maximum_value
-                    );
                     continue;
                 }
                 if amount_to_send < channel_update.htlc_minimum_value {
-                    debug!(
-                        "amount_to_send is less than htlc_minimum_value: {:?} min_value: {:?}",
-                        amount_to_send, channel_update.htlc_minimum_value
-                    );
                     continue;
                 }
                 let incoming_htlc_expiry = cur_hop.incoming_htlc_expiry
@@ -727,7 +719,6 @@ where
                     );
 
                 if probability < DEFAULT_MIN_PROBABILITY {
-                    debug!("probability is too low: {:?}", probability);
                     continue;
                 }
                 let agg_weight =
diff --git a/src/fiber/tests/graph.rs b/src/fiber/tests/graph.rs
index c121ec0f..bb792cae 100644
--- a/src/fiber/tests/graph.rs
+++ b/src/fiber/tests/graph.rs
@@ -863,8 +863,77 @@ fn test_graph_payment_pay_self_with_one_node() {
 fn test_graph_build_route_with_double_edge_node() {
     let mut network = MockNetworkGraph::new(3);
     // Add edges with min_htlc_value set to 50
-    network.add_edge_with_config(0, 2, Some(500), Some(500), Some(50), None, None, Some(100));
-    network.add_edge_with_config(2, 0, Some(500), Some(300), Some(50), None, None, Some(200));
+    // A <-> B, A is initiator, and A -> B with fee rate 5000, B -> A with fee rate 600000
+    network.add_edge_with_config(
+        0,
+        2,
+        Some(500),
+        Some(5000),
+        Some(50),
+        None,
+        None,
+        Some(600000),
+    );
+    // A -> B, B is initiator, B -> A with fee rate 100000, A -> B with fee rate 200
+    network.add_edge_with_config(
+        2,
+        0,
+        Some(500),
+        Some(100000),
+        Some(50),
+        None,
+        None,
+        Some(200),
+    );
+
+    let node0 = network.keys[0];
+
+    // node0 is the source node
+    let command = SendPaymentCommand {
+        target_pubkey: Some(network.keys[0].into()),
+        amount: Some(100),
+        payment_hash: Some(Hash256::default()),
+        final_htlc_expiry_delta: Some(100),
+        invoice: None,
+        timeout: Some(10),
+        max_fee_amount: Some(1000),
+        max_parts: None,
+        keysend: Some(false),
+        udt_type_script: None,
+        allow_self_payment: true,
+    };
+    let payment_data = SendPaymentData::new(command, node0.into()).unwrap();
+    let route = network.graph.build_route(&payment_data);
+    assert!(route.is_ok());
+}
+
+#[test]
+fn test_graph_build_route_with_other_node_maybe_better() {
+    let mut network = MockNetworkGraph::new(3);
+    // Add edges with min_htlc_value set to 50
+    // A <-> B, A is initiator, and A -> B with fee rate 5000, B -> A with fee rate 600000
+    network.add_edge_with_config(
+        0,
+        2,
+        Some(500),
+        Some(600000),
+        Some(50),
+        None,
+        None,
+        Some(600000),
+    );
+    // A -> B, B is initiator, B -> A with fee rate 100000, A -> B with fee rate 200
+    network.add_edge_with_config(
+        2,
+        0,
+        Some(500),
+        Some(100000),
+        Some(50),
+        None,
+        None,
+        Some(600000),
+    );
+    // B <-> C, B is initiator
     network.add_edge_with_config(2, 3, Some(500), Some(2), Some(50), None, None, Some(1));
 
     let node0 = network.keys[0];