diff --git a/src/midjourney.message.ts b/src/midjourney.message.ts
index 4200ec7..bfe89d1 100644
--- a/src/midjourney.message.ts
+++ b/src/midjourney.message.ts
@@ -1,7 +1,9 @@
 import axios from "axios";
 import { MJMessage } from "./interfaces";
+import { CreateQueue } from "./queue";
 
 export class MidjourneyMessage {
+  private magApiQueue = CreateQueue(1);
   constructor(
     public ChannelId: string,
     protected SalaiToken: string,
@@ -19,7 +21,7 @@ export class MidjourneyMessage {
     loading?: (uri: string) => void,
     options?: string
   ) {
-    const data = await this.RetrieveMessages(this.Limit);
+    const data = await this.safeRetrieveMessages(this.Limit);
     for (let i = 0; i < data.length; i++) {
       const item = data[i];
       if (
@@ -35,7 +37,6 @@ export class MidjourneyMessage {
           this.log("no attachment");
           break;
         }
-
         const imageUrl = item.attachments[0].url;
         if (!imageUrl.endsWith(".png")) {
           loading && loading(imageUrl);
@@ -66,6 +67,7 @@ export class MidjourneyMessage {
       await this.Wait(1000 * 2);
     }
   }
+
   async WaitOptionMessage(
     content: string,
     options: string,
@@ -85,6 +87,23 @@ export class MidjourneyMessage {
     return new Promise((resolve) => setTimeout(resolve, ms));
   }
 
+  // limit the number of concurrent interactions
+  protected async safeRetrieveMessages(limit = 50) {
+    const item: any = await new Promise((resolve, reject) => {
+      this.magApiQueue.push(
+        {
+          task: this.RetrieveMessages.bind(this, limit),
+          callback: (data) => {
+            resolve(data);
+          },
+        },
+        (err) => {
+          reject(err);
+        }
+      );
+    });
+    return item;
+  }
   async RetrieveMessages(limit = 50) {
     const headers = { authorization: this.SalaiToken };
     const response = await axios.get(
diff --git a/src/midjourney.ts b/src/midjourney.ts
index ebc5af5..c3c33dc 100644
--- a/src/midjourney.ts
+++ b/src/midjourney.ts
@@ -2,10 +2,8 @@ import axios from "axios";
 import { MidjourneyMessage } from "./midjourney.message";
 import { CreateQueue, QueueTask } from "./queue";
 import { random, sleep } from "./utls";
-import { QueueObject, tryEach } from "async";
-
 export class Midjourney extends MidjourneyMessage {
-  ApiQueue: QueueObject<QueueTask<any>>;
+  private ApiQueue = CreateQueue(1);
   constructor(
     public ServerId: string,
     public ChannelId: string,
@@ -13,8 +11,6 @@ export class Midjourney extends MidjourneyMessage {
     public debug = false
   ) {
     super(ChannelId, SalaiToken, debug);
-    this.log("Midjourney constructor");
-    this.ApiQueue = CreateQueue(1);
   }
 
   async Imagine(prompt: string, loading?: (uri: string) => void) {
@@ -52,7 +48,7 @@ export class Midjourney extends MidjourneyMessage {
 
   protected async interactions(
     payload: any,
-    callback: (result: number) => void
+    callback?: (result: number) => void
   ) {
     const headers = { authorization: this.SalaiToken };
     const t0 = performance.now();
diff --git a/src/queue.ts b/src/queue.ts
index dca20c7..ec1485f 100644
--- a/src/queue.ts
+++ b/src/queue.ts
@@ -4,21 +4,6 @@ export interface QueueTask<T> {
   task: TaskFunction<T>;
   callback?: (result: T) => void;
 }
-// const queue = async.queue(async ({ task, callback }: QueueTask<any>) => {
-//   const result = await task();
-//   callback(result);
-// }, 10);
-
-// const task1: TaskFunction<number> = async () => {
-//   // do some async work
-//   return 42;
-// };
-// queue.push({
-//   task: task1,
-//   callback: (result: number) => {
-//     console.log(result); // output: 42
-//   },
-// });
 export function CreateQueue<T>(concurrency: number) {
   return async.queue(async ({ task, callback }: QueueTask<any>) => {
     const result = await task();