UPDATE

app.py

@@ -169,7 +169,7 @@ async def audio_handler(event):
         file_path = await client.download_media(event.message, f"downloads/{event.sender.id}_audio.mp3")
         return await msg.edit("`Downloaded successfully...`")
     elif event.is_group and event.text.startswith("/edit") and reply:
-        if reply.media and reply.message.media.document.mime_type.startswith('audio'):
+        if reply.media and reply.media.document.mime_type.startswith('audio'):
             msg = await event.reply("`Downloading...`")
             file_path = await reply.download_media(f"downloads/{event.sender.id}_audio.mp3")
             # try: