UPDATE

app.py

@@ -140,6 +140,7 @@ client = TelegramClient('session_name', API_ID, API_HASH)
 # Define the states for user interaction
 states = {}
 
+@client.on(events.NewMessage(pattern='/start'))
 async def start_handler(event):
     await event.reply("Welcome to AudioFusion Bot! Send me an audio file, and I'll apply effects for you.")
 
@@ -151,6 +152,7 @@ buttons = [
         [Button.inline('Send', b'send')],
     ]
 
+@client.on(events.NewMessage(pattern='/buttons'))
 async def buttons_handler(event):
     user_id = event.sender_id
         
@@ -170,6 +172,7 @@ async def buttons_handler(event):
     await client.send_file(event.chat_id, file="image.jpg", caption="Preview the current modification:", buttons=buttons)
     
 
+@client.on(events.CallbackQuery(pattern=b'(slowed|8d|reverb|reverse|trim|volume|speedup)'))
 async def audio_effect_handler(event):
     user_id = event.sender_id
     if user_id not in states or not states[user_id]:
@@ -207,6 +210,7 @@ async def audio_effect_handler(event):
         await event.reply(f"An error occurred: {str(e)}")
 
 
+@client.on(events.CallbackQuery(pattern=b'preview'))
 async def preview_handler(event):
     user_id = event.sender_id
     if user_id in states and states[user_id]:
@@ -223,6 +227,7 @@ async def preview_handler(event):
         await event.answer("No modified audio file found. Please apply an effect first.")
 
 
+@client.on(events.CallbackQuery(pattern=b'send'))
 async def send_handler(event):
     user_id = event.sender_id
     if user_id in states and states[user_id]:
@@ -240,12 +245,6 @@ async def send_handler(event):
 
 
 
-# Register command and button handlers
-client.on(events.NewMessage(pattern='/start')(start_handler))
-client.on(events.NewMessage(pattern='/buttons')(buttons_handler))
-client.on(events.CallbackQuery(pattern=b'(slowed|8d|reverb|reverse|trim|volume|speedup)')(audio_effect_handler))
-client.on(events.CallbackQuery(pattern=b'preview')(preview_handler))
-client.on(events.CallbackQuery(pattern=b'send')(send_handler))
 
 async def initiation():
     await client.send_message(-1001662130485, "**Hugging is Running.**", buttons=[(Button.url("Execal", "https://t.me/execal"),)],)