diff --git a/onchain/tokens/metadata.py b/onchain/tokens/metadata.py
index 32db697..3e98d21 100644
--- a/onchain/tokens/metadata.py
+++ b/onchain/tokens/metadata.py
@@ -175,9 +175,9 @@ async def _search_token_on_dexscreener(
 
                 # Filter by chain if specified
                 if chain:
-                    pairs = [pair for pair in pairs if pair["chainId"] == chain]
-                if len(pairs) == 0:
-                    return None
+        chain = chain.lower()
+        if chain not in SUPPORTED_CHAINS:
+            return None
 
                 token_address = pairs[0]["baseToken"]["address"]
                 token_chain = pairs[0]["chainId"]