diff --git a/handlers/error.py b/handlers/error.py
index f2bd706..7464256 100644
--- a/handlers/error.py
+++ b/handlers/error.py
@@ -53,6 +53,10 @@ class ErrorHandler(commands.Cog):
         self._old_tree_error = tree.on_error
         tree.on_error = self.on_app_command_error
 
+    async def cog_unload(self):
+        tree = self.bot.tree
+        tree.on_error = self._old_tree_error
+
     async def on_app_command_error(
         self,
         interaction: discord.Interaction,
diff --git a/lib/checks.py b/lib/checks.py
index 09d58f8..9443b10 100644
--- a/lib/checks.py
+++ b/lib/checks.py
@@ -1,19 +1,19 @@
-from discord.ext import commands
+import discord
+from discord import app_commands
 
 from lib.exceptions import BirthdaysDisabled
 from services.config_service import GuildConfig
 
 
 def birthdays_enabled():
-    async def predicate(ctx: commands.Context[commands.Bot]) -> bool:
-        if ctx.guild is None:
+    async def predicate(interaction: discord.Interaction) -> bool:
+        if interaction.guild is None:
             return True
 
-        guild_config = GuildConfig(ctx.guild.id)
-
-        if not guild_config.birthday_channel_id:
+        guild_config = GuildConfig(interaction.guild.id)
+        if guild_config.birthday_channel_id is None:
             raise BirthdaysDisabled
 
         return True
 
-    return commands.check(predicate)
+    return app_commands.check(predicate)
diff --git a/lib/exceptions.py b/lib/exceptions.py
index 792b0aa..3a21630 100644
--- a/lib/exceptions.py
+++ b/lib/exceptions.py
@@ -1,9 +1,10 @@
+from discord import app_commands
 from discord.ext import commands
 
 from lib.const import CONST
 
 
-class BirthdaysDisabled(commands.CheckFailure):
+class BirthdaysDisabled(commands.CheckFailure, app_commands.CheckFailure):
     """
     Raised when the birthdays module is disabled in ctx.guild.
     """