diff --git a/pyproject.toml b/pyproject.toml
index 7a6383b6..9d0bc3a6 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -39,7 +39,7 @@ dependencies = [
     "tensorflow==2.12.0",
     "typer[all]==0.9.0",
     "pydantic==2.7.0",
-    "ray[rllib] == 2.8.0",
+    "ray[rllib] == 2.8.0, < 3",
     "ipywidgets"
 ]
 
diff --git a/src/primaite/game/agent/observations/observations.py b/src/primaite/game/agent/observations/observations.py
index 0d6ff2a3..518fdf9f 100644
--- a/src/primaite/game/agent/observations/observations.py
+++ b/src/primaite/game/agent/observations/observations.py
@@ -1,6 +1,6 @@
 """Manages the observation space for the agent."""
 from abc import ABC, abstractmethod
-from typing import Any, Dict, Iterable, Type
+from typing import Any, Dict, Iterable, Type, Optional, Union
 
 from gymnasium import spaces
 from gymnasium.core import ObsType
@@ -9,7 +9,7 @@ from pydantic import BaseModel, ConfigDict
 from primaite import getLogger
 
 _LOGGER = getLogger(__name__)
-WhereType = Iterable[str | int] | None
+WhereType = Optional[Iterable[Union[str, int]]]
 
 
 class AbstractObservation(ABC):
diff --git a/src/primaite/game/agent/rewards.py b/src/primaite/game/agent/rewards.py
index 726afaa4..0222bfcc 100644
--- a/src/primaite/game/agent/rewards.py
+++ b/src/primaite/game/agent/rewards.py
@@ -26,7 +26,7 @@ the structure:
 ```
 """
 from abc import abstractmethod
-from typing import Callable, Dict, Iterable, List, Optional, Tuple, Type, TYPE_CHECKING
+from typing import Callable, Dict, Iterable, List, Optional, Tuple, Type, TYPE_CHECKING, Union
 
 from typing_extensions import Never
 
@@ -37,7 +37,7 @@ if TYPE_CHECKING:
     from primaite.game.agent.interface import AgentActionHistoryItem
 
 _LOGGER = getLogger(__name__)
-WhereType = Iterable[str | int] | None
+WhereType = Optional[Iterable[Union[str, int]]]
 
 
 class AbstractReward: