diff --git a/core/llm/anthropic_client.py b/core/llm/anthropic_client.py
index e2a41e9d..f458a7b2 100644
--- a/core/llm/anthropic_client.py
+++ b/core/llm/anthropic_client.py
@@ -116,7 +116,11 @@ class AnthropicClient(BaseLLMClient):
         except ValueError:
             return datetime.timedelta(seconds=5)
 
-        now = datetime.datetime.now(tz=zoneinfo.ZoneInfo("UTC"))
+        try:
+            now = datetime.datetime.now(tz=zoneinfo.ZoneInfo("UTC"))
+        except zoneinfo.ZoneInfoNotFoundError:
+            now = datetime.datetime.now(tz=datetime.timezone.utc)
+
         return reset_time - now