diff --git a/srcs/requirements/nestjs/api_back/src/chat/chat.controller.ts b/srcs/requirements/nestjs/api_back/src/chat/chat.controller.ts
index 90160166..e97eb6bb 100644
--- a/srcs/requirements/nestjs/api_back/src/chat/chat.controller.ts
+++ b/srcs/requirements/nestjs/api_back/src/chat/chat.controller.ts
@@ -52,7 +52,17 @@ export class ChatController {
 
 		let fields = ["name", "type", "users", "protection", "allowed_users"];
 		const rooms = await this.chatService.getMyRooms(req.user.username, fields);
+		if (!rooms)
+		{
+			printCallerError(`controllerror: true, code: 'ROOMS_NOT_FOUND', message: 'rooms not found for ${req.user.username}'`);
+			throw new HttpException({ error: true, code: 'ROOMS_NOT_FOUND', message: `rooms not found for ${req.user.username}` }, HttpStatus.UNPROCESSABLE_ENTITY);
+		}
 		const blocked = await this.chatService.getListBlockUser(req.user.username);
+		if (!blocked)
+		{
+			printCallerError(`controllerror: true, code: 'USERS_NOT_FOUND', message: 'blocked users not found for ${req.user.username}'`);
+			throw new HttpException({ error: true, code: 'USERS_NOT_FOUND', message: `blocked users not found for ${req.user.username}` }, HttpStatus.UNPROCESSABLE_ENTITY);
+		}
 
 		let filtered_rooms = rooms.filter(room =>
 		{
@@ -284,6 +294,12 @@ export class ChatController {
 		let fields = ["protection", "allowed_users", "type", "users"];
 		const room_db = await this.chatService.getRoomByName(room.name, fields);
 
+		if (!room_db.users.includes(req.user.username))
+		{
+			console.log("throw error: error: true, code: 'NEED_JOIN', message: 'you didn't join this room'");
+			throw new HttpException({ error: true, code: 'NEED_JOIN', message: `you didn't join this room` }, HttpStatus.UNAUTHORIZED);
+		}
+
 		if (room_db.protection === true)
 		{
 			if (!room_db.allowed_users.includes(req.user.username))
@@ -445,10 +461,10 @@ export class ChatController {
 
 		// leaving message
 		let socket: socketDto = this.chatService.getSocket(req.user.username);
-		await messages.forEach(async (message) =>
+		await messages.forEach((message) =>
 		{
-			await this.chatService.addMessageToRoom(room_name, "SERVER", message);
-			await socket.to(socket.room).emit('message', "SERVER", message);
+			this.chatService.addMessageToRoom(room_name, "SERVER", message);
+			socket.to(socket.room).emit('message', "SERVER", message);
 		});
 		await socket.leave(socket.room);
 
diff --git a/srcs/requirements/nestjs/api_back/src/chat/chat.service.ts b/srcs/requirements/nestjs/api_back/src/chat/chat.service.ts
index 891ee5da..278cea30 100644
--- a/srcs/requirements/nestjs/api_back/src/chat/chat.service.ts
+++ b/srcs/requirements/nestjs/api_back/src/chat/chat.service.ts
@@ -65,6 +65,9 @@ export class ChatService {
 	async getMyRooms(username: string, fieldsToReturn: string[] = null): Promise<Chatroom[]>
 	{
 		printCaller("-- in ");
+		
+		console.log("---- username:", username)
+		console.log("---- all rooms:", await this.getAllRooms());
 
 		//await this.sleep(1000);
 		let rooms: Chatroom[];
@@ -648,6 +651,8 @@ export class ChatService {
 	async removeUserFromRoom(username: string, room_name: string): Promise<string[]>
 	{
 		printCaller("-- in ");
+		console.log("---- username:", username);
+		console.log("---- room_name:", room_name);
 
 		let messages = [`${username} left the room`];
 
@@ -687,7 +692,10 @@ export class ChatService {
 			else
 				room.owner = "";
 		}
+		console.log("---- room:", room);
 		await this.chatroomRepository.save(room);
+		
+		console.log("---- all rooms:", await this.getAllRooms());
 
 		printCaller("-- out ");
 		return messages;
@@ -940,7 +948,6 @@ export class ChatService {
 		});
 
 		let socket = this.getSocket(old_name);
-		printCaller("----------- socket", socket);
 		if (socket)
 		{
 			this.removeSocket(old_name);
diff --git a/srcs/requirements/svelte/api_front/src/pieces/chat/Layout_home.svelte b/srcs/requirements/svelte/api_front/src/pieces/chat/Layout_home.svelte
index eeb992fa..2eeabaef 100644
--- a/srcs/requirements/svelte/api_front/src/pieces/chat/Layout_home.svelte
+++ b/srcs/requirements/svelte/api_front/src/pieces/chat/Layout_home.svelte
@@ -1,13 +1,18 @@
-<script>
+<script lang="ts">
 
 	import { layout, msgs, user, current_room } from './Store_chat';
 	import { change_room, get_room_messages, get_my_rooms } from './Request_rooms';
 	import { to_print } from './Utils_chat';
 	import { onMount } from 'svelte';
 	import Button from './Element_button.svelte';
+	import type { FetchResponse } from './Types_chat';
+	import Warning from './Element_warning.svelte';
 
 	let rooms = get_my_rooms();
 
+	let response: FetchResponse;
+	let show_error = false;
+
 	// go to clicked room
 	async function go_to_room(room)
 	{
@@ -21,8 +26,11 @@
 		}
 		else
 		{
-			await change_room(room);
-			await get_room_messages();
+			response = await change_room(room);
+
+			// print error message
+			if (response.status >= 300 || response.error)
+				show_error = response.error;
 		}
 	}
 
@@ -47,6 +55,9 @@
 
 	<!-- panel home -->
 	<div class="panel panel_home __border_top">
+		{#if show_error}
+			<Warning content={response.message}/>
+		{/if}
 		<p class="title">list of your rooms :</p>
 		<div class="room_list">
 			<div class="__show_if_only_child">
diff --git a/srcs/requirements/svelte/api_front/src/pieces/chat/Request_rooms.ts b/srcs/requirements/svelte/api_front/src/pieces/chat/Request_rooms.ts
index f12809f0..7791db20 100644
--- a/srcs/requirements/svelte/api_front/src/pieces/chat/Request_rooms.ts
+++ b/srcs/requirements/svelte/api_front/src/pieces/chat/Request_rooms.ts
@@ -45,13 +45,16 @@ export async function join_room(room: Room)
 	return response.room;
 }
 
-export async function change_room(room: Room)
+export async function change_room(room: Room): Promise<FetchResponse>
 {
 	to_print("in change_room");
 
 	to_print("room sent to change:", room);
 	let response: FetchResponse = await fetch_chat_request('change', FetchMethod.POST, room);
-	to_print("room returned from change:", response.room);
+	to_print("room returned from change:", response);
+
+	if (response.status >= 300 || response.error)
+		return response;
 
 	await get_room_messages();
 
@@ -59,6 +62,8 @@ export async function change_room(room: Room)
 
 	current_room.set(room);
 	layout.set("room");
+
+	return response;
 }
 
 export async function validate_password(room: Room)