diff --git a/library/LibMysqlHelper.js b/library/LibMysqlHelper.js
index a7e0b1a..9869f37 100755
--- a/library/LibMysqlHelper.js
+++ b/library/LibMysqlHelper.js
@@ -2,7 +2,7 @@ const db = require(`../config/dbMysqlConn`);
 // const Promise = require("bluebird");
 
 class MysqlHelpers {
-  static async insert (table, data) {
+  static async insert(table, data) {
     return new Promise((resolve, reject) => {
       const query = `INSERT INTO ${table} SET ?;`;
       db.getConnection(function (err, conn) {
@@ -42,7 +42,7 @@ class MysqlHelpers {
       });
     })
   }
-  static async update (table, data, colId, valId) {
+  static async update(table, data, colId, valId) {
     return new Promise((resolve, reject) => {
       const query = `UPDATE ${table} SET ? WHERE ${colId} = ?;`;
       db.getConnection(function (err, conn) {
@@ -81,7 +81,7 @@ class MysqlHelpers {
       });
     })
   }
-  static async delete (table, colId, valId) {
+  static async delete(table, colId, valId) {
     return new Promise((resolve, reject) => {
       const query = `DELETE FROM ${table} WHERE ${colId} = ?;`;
       db.getConnection(function (err, conn) {
@@ -120,7 +120,7 @@ class MysqlHelpers {
       });
     })
   }
-  static async createConnection () {
+  static async createConnection() {
     return new Promise((resolve, reject) => {
       db.getConnection(function (err, conn) {
         if (err) {
@@ -132,18 +132,18 @@ class MysqlHelpers {
       });
     })
   }
-  static async getDbMysqlConn () {
+  static async getDbMysqlConn() {
     return new Promise((resolve, reject) => {
       resolve(db);
     })
   }
-  static async releaseConnection (conn) {
+  static async releaseConnection(conn) {
     return new Promise((resolve, reject) => {
       if (conn) conn.release();
       resolve(true);
     })
   }
-  static async createTrx (conn) {
+  static async createTrx(conn) {
     return new Promise((resolve, reject) => {
       conn.beginTransaction(async function (err) {
         if (err) {
@@ -155,7 +155,7 @@ class MysqlHelpers {
       });
     })
   }
-  static async queryTrx (conn, query = '', params = []) {
+  static async queryTrx(conn, query = '', params = []) {
     return new Promise((resolve, reject) => {
       conn.query(query, params, function (err, result) {
         if (err) {
@@ -170,7 +170,7 @@ class MysqlHelpers {
       });
     })
   }
-  static async query (conn, query = '', params = []) {
+  static async query(conn, query = '', params = []) {
     return new Promise((resolve, reject) => {
       conn.query(query, params, function (err, result) {
         if (err) return reject(err);
@@ -179,7 +179,7 @@ class MysqlHelpers {
       });
     })
   }
-  static async commit (conn) {
+  static async commit(conn) {
     return new Promise((resolve, reject) => {
       conn.commit(async function (err) {
         if (err) {
@@ -192,13 +192,24 @@ class MysqlHelpers {
       });
     })
   }
-  static async rollback (conn) {
-    return new Promise((resolve, reject) => {
-      conn.rollback(async function () {
-        conn.release();
-        reject(err);
-      });
-      return false;
+  // static async rollback (conn) {
+  //   return new Promise((resolve, reject) => {
+  //     conn.rollback(async function () {
+  //       conn.release();
+  //       reject(err);
+  //     });
+  //     return false;
+  //   })
+  // }
+  static async rollback(conn) {
+    return new Promise((resolve) => {
+      conn.rollback(() => {
+        try {
+          conn.release()
+        } catch (e) { }
+
+        resolve(true)
+      })
     })
   }
 }
diff --git a/models/GpsTracksModels.js b/models/GpsTracksModels.js
index 6d6f95b..57b1a9d 100755
--- a/models/GpsTracksModels.js
+++ b/models/GpsTracksModels.js
@@ -256,6 +256,141 @@ class GpsTracksModels {
 	// 	})
 	// }
 
+	/** MUTEX ESPECIALLY FOR RLTM  */
+
+	// static bundleCreate2(logs = {}, rltm = {}) {
+	// 	return new Promise(async (resolve, reject) => {
+	// 		let lock = null
+	// 		try {
+	// 			const conn = await MysqlHelpers.createConnection()
+	// 			await MysqlHelpers.createTrx(conn)
+
+	// 			let rltmLength = Object.keys(rltm).length
+	// 			let resLogs = undefined
+
+	// 			if (Object.keys(logs).length > 0) {
+	// 				resLogs = await MysqlHelpers.queryTrx(
+	// 					conn,
+	// 					`INSERT INTO t_gps_tracks SET ?;`,
+	// 					[logs],
+	// 				)
+
+	// 				if (logs.action == "location") {
+	// 					const date = logs.crt_d
+	// 					const mm = moment.unix(date).format("MM")
+	// 					const yy = moment.unix(date).format("YY")
+	// 					logs.id = resLogs.insertId
+
+	// 					try {
+	// 						await MysqlHelpers.queryTrx(
+	// 							conn,
+	// 							`
+	// 							INSERT INTO tracks_${yy}${mm}
+	// 							SET ?	
+	// 						`,
+	// 							[logs],
+	// 						)
+	// 					} catch (error) {
+	// 						console.log(error)
+	// 						fs.appendFileSync(
+	// 							path.join(__dirname, `error_data_log.txt`),
+	// 							JSON.stringify(logs) + `\n`,
+	// 						)
+	// 					}
+	// 				}
+	// 			}
+
+	// 			if (rltmLength > 0 && typeof resLogs !== "undefined")
+	// 				rltm.master_id = resLogs.insertId
+
+	// 			if (
+	// 				rltmLength > 0 &&
+	// 				rltm.latitude !== null &&
+	// 				rltm.longitude !== null
+	// 			) {
+	// 				// === KUNCI DI SINI ===
+	// 				// Lock per device_id supaya SELECT-DELETE-INSERT untuk
+	// 				// device yang sama tidak berjalan bersamaan dari request/worker
+	// 				// lain. Inilah yang tadinya memicu ER_DUP_ENTRY dan
+	// 				// "Lock wait timeout" karena banyak transaksi menumpuk
+	// 				// menunggu baris yang sama.
+	// 				lock = await rltmMutex.lock(`t_gps_tracks_rltm:${rltm.device_id}`, {
+	// 					duration: 50000,  // maksimal lock dipegang 5 detik
+	// 					maxWait: 50000,  // menunggu lock maksimal 10 detik lalu error
+	// 				})
+
+	// 				let devices = await MysqlHelpers.queryTrx(
+	// 					conn,
+	// 					`SELECT id FROM t_gps_tracks_rltm as rltm WHERE rltm.device_id = ?`,
+	// 					[rltm.device_id],
+	// 				)
+	// 				if (devices.length > 1)
+	// 					await MysqlHelpers.queryTrx(
+	// 						conn,
+	// 						`DELETE from t_gps_tracks_rltm WHERE device_id = ?;`,
+	// 						[rltm.device_id],
+	// 					)
+
+	// 				if (rltm.vhc_id != 0) {
+	// 					let vhcs = await MysqlHelpers.queryTrx(
+	// 						conn,
+	// 						`SELECT id FROM t_gps_tracks_rltm as rltm WHERE rltm.vhc_id = ?`,
+	// 						[rltm.vhc_id],
+	// 					)
+	// 					if (vhcs.length > 1)
+	// 						await MysqlHelpers.queryTrx(
+	// 							conn,
+	// 							`DELETE from t_gps_tracks_rltm WHERE vhc_id = ?;`,
+	// 							[rltm.vhc_id],
+	// 						)
+	// 				}
+
+	// 				if (rltm.drv_id != 0) {
+	// 					let drvs = await MysqlHelpers.queryTrx(
+	// 						conn,
+	// 						`SELECT id FROM t_gps_tracks_rltm as rltm WHERE rltm.drv_id = ?`,
+	// 						[rltm.drv_id],
+	// 					)
+	// 					if (drvs.length > 1)
+	// 						await MysqlHelpers.queryTrx(
+	// 							conn,
+	// 							`DELETE from t_gps_tracks_rltm WHERE drv_id = ?;`,
+	// 							[rltm.drv_id],
+	// 						)
+	// 				}
+
+	// 				await MysqlHelpers.queryTrx(
+	// 					conn,
+	// 					`INSERT INTO t_gps_tracks_rltm SET ? ON DUPLICATE KEY UPDATE ?;`,
+	// 					[rltm, rltm],
+	// 				)
+	// 			}
+
+	// 			await MysqlHelpers.commit(conn)
+
+	// 			resolve({
+	// 				type: "success",
+	// 				result: resLogs,
+	// 			})
+	// 		} catch (err) {
+	// 			console.log("ERROR bundleCreate2 : " + rltm.device_id)
+	// 			reject(err)
+	// 		} finally {
+	// 			// Lock selalu dilepas, baik sukses maupun gagal,
+	// 			// supaya tidak deadlock request device yang sama berikutnya.
+	// 			if (lock) {
+	// 				try {
+	// 					await rltmMutex.unlock(lock)
+	// 				} catch (unlockErr) {
+	// 					console.log("ERROR unlock mutex : " + rltm.device_id, unlockErr)
+	// 				}
+	// 			}
+	// 		}
+	// 	})
+	// }
+
+	/** MUTEX FOR ALL REQUEST */
+
 	static bundleCreate2(logs = {}, rltm = {}) {
 		return new Promise(async (resolve, reject) => {
 			let lock = null
@@ -273,28 +408,38 @@ class GpsTracksModels {
 						[logs],
 					)
 
-					if (logs.action == "location") {
-						const date = logs.crt_d
-						const mm = moment.unix(date).format("MM")
-						const yy = moment.unix(date).format("YY")
-						logs.id = resLogs.insertId
+					let trackLock = null
+
+					try {
+						if (logs.action == "location") {
+
+							trackLock = await rltmMutex.lock(
+								`tracks_insert:${logs.device_id}`,
+								{
+									duration: 90000,
+									maxWait: 90000,
+								}
+							)
+
+							const date = logs.crt_d
+							const mm = moment.unix(date).format("MM")
+							const yy = moment.unix(date).format("YY")
+
+							logs.id = resLogs.insertId
 
-						try {
 							await MysqlHelpers.queryTrx(
 								conn,
 								`
-								INSERT INTO tracks_${yy}${mm}
-								SET ?	
-							`,
-								[logs],
-							)
-						} catch (error) {
-							console.log(error)
-							fs.appendFileSync(
-								path.join(__dirname, `error_data_log.txt`),
-								JSON.stringify(logs) + `\n`,
+            INSERT INTO tracks_${yy}${mm}
+            SET ?
+            `,
+								[logs]
 							)
 						}
+					} finally {
+						if (trackLock) {
+							await rltmMutex.unlock(trackLock)
+						}
 					}
 				}