diff --git a/signalbot/bot.py b/signalbot/bot.py
index 069ac5f..ab806fd 100644
--- a/signalbot/bot.py
+++ b/signalbot/bot.py
@@ -338,8 +338,8 @@ async def _produce(self, name: int) -> None:
     def _should_react_for_contact(
         self,
         message: Message,
-        contacts: list[str] | bool,
-        group_ids: list[str] | bool,
+        contacts: Union[list[str], bool],
+        group_ids: Union[list[str], bool],
     ):
         """Is the command activated for a certain chat or group?"""
 
@@ -379,7 +379,7 @@ def _should_react_for_contact(
     def _should_react_for_lambda(
         self,
         message: Message,
-        f: Callable[[Message], bool] | None,
+        f: Optional[Callable[[Message], bool]] = None,
     ) -> bool:
         if f is None:
             return True