diff --git a/flow/envs/multiagent/i210.py b/flow/envs/multiagent/i210.py
index 004208cb4..65bad3e37 100644
--- a/flow/envs/multiagent/i210.py
+++ b/flow/envs/multiagent/i210.py
@@ -380,7 +380,7 @@ def step(self, rl_actions):
         state, reward, done, info = super().step(rl_actions)
         # handle the edge case where a vehicle hasn't been put back when the rollout terminates
         if self.reroute_on_exit and done['__all__']:
-            for rl_id in self.observed_rl_ids:
+            for rl_id in self._observed_rl_ids:
                 if rl_id not in state.keys():
                     done[rl_id] = True
                     reward[rl_id] = 0