diff --git a/bridge/src/messages/wrapped-event.ts b/bridge/src/messages/wrapped-event.ts
index c02c0b2..8629d19 100644
--- a/bridge/src/messages/wrapped-event.ts
+++ b/bridge/src/messages/wrapped-event.ts
@@ -16,7 +16,7 @@ export class WrappedEvent extends WrappingEvent {
     private readonly _refundTxId: string | null;
     private readonly _isWhitelistEvent: boolean;
     private readonly _description: string | undefined;
-    private readonly _feeTransferTxId: TxId;
+    private readonly _feeTransferTxId: TxId | null;
 
     constructor(
         explorerUrl: string,
@@ -33,7 +33,7 @@ export class WrappedEvent extends WrappingEvent {
         refundTxId: TxId | null,
         isWhitelistEvent: boolean,
         description: string | undefined,
-        feeTransferTxId: TxId
+        feeTransferTxId: TxId | null
     ) {
         super(explorerUrl, ncscanUrl, useNcscan, etherscanUrl);
 
@@ -64,6 +64,15 @@ export class WrappedEvent extends WrappingEvent {
                       },
                   ]
                 : [];
+        const feeTransferTxIdField =
+            this._feeTransferTxId !== null
+                ? [
+                      {
+                          title: "9c network transaction (fee transfer)",
+                          value: this.toExplorerUrl(this._feeTransferTxId),
+                      },
+                  ]
+                : [];
 
         let text = "NCG → wNCG event occurred.";
         if (this._isWhitelistEvent) text += " (Whitelist Transfer) <!here>";
@@ -101,10 +110,7 @@ export class WrappedEvent extends WrappingEvent {
                             title: "fee",
                             value: this._fee.toString(),
                         },
-                        {
-                            title: "9c network transaction (fee transfer)",
-                            value: this.toExplorerUrl(this._feeTransferTxId),
-                        },
+                        ...feeTransferTxIdField,
                         ...refundFields,
                     ],
                     fallback: `NCG ${this._sender} → wNCG ${this._recipient}`,
diff --git a/bridge/src/messages/wrapping-event.ts b/bridge/src/messages/wrapping-event.ts
index 907b402..40b960d 100644
--- a/bridge/src/messages/wrapping-event.ts
+++ b/bridge/src/messages/wrapping-event.ts
@@ -1,8 +1,6 @@
 import { ChatPostMessageArguments } from "@slack/web-api";
 import { Message } from ".";
 import { TxId } from "../types/txid";
-import { URL } from "url";
-import { join, resolve } from "path";
 import { ForceOmit } from "../types/force-omit";
 import { combineNcExplorerUrl, combineUrl } from "./utils";
 
diff --git a/bridge/src/observers/nine-chronicles.ts b/bridge/src/observers/nine-chronicles.ts
index 29187cf..2915124 100644
--- a/bridge/src/observers/nine-chronicles.ts
+++ b/bridge/src/observers/nine-chronicles.ts
@@ -407,7 +407,7 @@ export class NCGTransferredEventObserver
         console.log("WNCG mint tx", transactionHash);
 
         // Transfer fee to the fee collector address if any
-        let feeTransferTxId: string = "No Fee Incurred";
+        let feeTransferTxId: string | null = null;
         if (fee.greaterThan(0)) {
             feeTransferTxId = await this._ncgTransfer.transfer(
                 this._feeCollectorAddress,
@@ -415,6 +415,8 @@ export class NCGTransferredEventObserver
                 "I'm bridge and the fee is sent to fee collector."
             );
             console.log("Fee transfer tx", feeTransferTxId);
+        } else {
+            console.log("No fee transfer");
         }
 
         const isWhitelistEvent: boolean = accountType !== ACCOUNT_TYPE.GENERAL;
diff --git a/bridge/test/messages/__snapshots__/wrapped-event.spec.ts.snap b/bridge/test/messages/__snapshots__/wrapped-event.spec.ts.snap
index 3dd5959..29a49d0 100644
--- a/bridge/test/messages/__snapshots__/wrapped-event.spec.ts.snap
+++ b/bridge/test/messages/__snapshots__/wrapped-event.spec.ts.snap
@@ -100,7 +100,7 @@ Object {
     Object {
       "author_name": "Bridge Event",
       "color": "#b547f5",
-      "fallback": "NCG 0xCbfC996ad185c61a031f40CeeE80a055e6D83005 → wNCG 0xDac65eCE9CB3E7a538773e08DE31F973233F064f",
+      "fallback": "NCG 0x27303a4c77c466fc5c631066d64516f1c9a28426 → wNCG 0x50a2aC5E97050bCC3A34dc27858B5DfDF77c4C83",
       "fields": Array [
         Object {
           "title": "9c network transaction",
@@ -112,11 +112,11 @@ Object {
         },
         Object {
           "title": "sender (NineChronicles)",
-          "value": "0xCbfC996ad185c61a031f40CeeE80a055e6D83005",
+          "value": "0x27303a4c77c466fc5c631066d64516f1c9a28426",
         },
         Object {
           "title": "recipient (Ethereum)",
-          "value": "0xDac65eCE9CB3E7a538773e08DE31F973233F064f",
+          "value": "0x50a2aC5E97050bCC3A34dc27858B5DfDF77c4C83",
         },
         Object {
           "title": "amount",
@@ -126,10 +126,6 @@ Object {
           "title": "fee",
           "value": "1",
         },
-        Object {
-          "title": "9c network transaction (fee transfer)",
-          "value": "https://explorer.libplanet.io/9c-internal/transaction?0x9360cd40682a91a71f0afbfac3dd381866cdb319dc01c13531dfe648f8a28bc8",
-        },
         Object {
           "title": "description",
           "value": "test description",
diff --git a/bridge/test/messages/wrapped-event.spec.ts b/bridge/test/messages/wrapped-event.spec.ts
index 9d100eb..28a87c4 100644
--- a/bridge/test/messages/wrapped-event.spec.ts
+++ b/bridge/test/messages/wrapped-event.spec.ts
@@ -85,8 +85,8 @@ describe("WrappedEvent", () => {
             const NCSCAN_URL = "https://9cscan.com";
             const USE_NCSCAN_URL = false;
             const ETHERSCAN_URL = "https://ropsten.etherscan.io";
-            const SENDER = "0xCbfC996ad185c61a031f40CeeE80a055e6D83005";
-            const RECIPIENT = "0xDac65eCE9CB3E7a538773e08DE31F973233F064f";
+            const SENDER = "0x27303a4c77c466fc5c631066d64516f1c9a28426";
+            const RECIPIENT = "0x50a2aC5E97050bCC3A34dc27858B5DfDF77c4C83";
             const AMOUNT = "200";
             const ETHEREUM_TRANSACTION_HASH =
                 "0x9360cd40682a91a71f0afbfac3dd381866cdb319dc01c13531dfe648f8a28bc8";
@@ -94,8 +94,7 @@ describe("WrappedEvent", () => {
                 "3409cdbaa24ec6f7c8d2c0f636325a2b2e9611e5e6df5c593cfcd299860d8044";
             const FEE = new Decimal(1);
             const IS_WHITELIST_EVENT = true;
-            const FEE_TRANSFER_TX_ID =
-                "0x9360cd40682a91a71f0afbfac3dd381866cdb319dc01c13531dfe648f8a28bc8";
+            const FEE_TRANSFER_TX_ID = null;
             expect(
                 new WrappedEvent(
                     EXPLORER_URL,