discord.py AFK 命令在我放置后立即删除 afk

Question

好的，所以我正在尝试执行此 afk 命令，它似乎确实有效，但是一旦我放置 afk，机器人就会将其删除， 我的 main.py 中有这个空字典：

client=commands.Bot(...)
client.afk={}

代码：

  @commands.command()
  async def afk(self, ctx, reason=None):
      self.client.afk[ctx.author]={'message': reason, 'time': ctx.message.created_at}
      await ctx.send("You are now afk.")

  @commands.Cog.listener()
  async def on_message(self, message):
    if message.author.bot:return
    elif message.author in self.client.afk:
      self.client.afk.pop(message.author)
      await message.channel.send(f"Welcome back {message.author.mention}!")
    elif message.mentions:
      for mention in message.mentions:
        mentioned_afk_user=self.client.afk.get(mention, None)
        if mentioned_afk_user:
          await message.channel.send(f"{message.author.mention}, **{mention.name}#{mention.discriminator}** has been AFK since <t:{int(mentioned_afk_user['time'].timestamp())}:R>, Reason: {mentioned_afk_user['message']}")

Output