Attempt to fix 'cannot verify guild_age' warning on large server

Author: raidensakura

bot.py

@@ -21,6 +21,7 @@
 from aiohttp import ClientSession, ClientResponseError
 from discord.ext import commands, tasks
 from discord.ext.commands.view import StringView
+from discord.ext.commands import MemberConverter
 from emoji import UNICODE_EMOJI
 from pkg_resources import parse_version
 
@@ -791,7 +792,7 @@ async def is_blocked(
         send_message: bool = False,
     ) -> bool:
 
-        member = self.guild.get_member(author.id)
+        member = self.guild.get_member(author.id) or await MemberConverter.convert(author)
         if member is None:
             # try to find in other guilds
             for g in self.guilds: