diff --git a/backend/services/database.py b/backend/services/database.py
index bf02305..692fb23 100644
--- a/backend/services/database.py
+++ b/backend/services/database.py
@@ -6169,6 +6169,15 @@ def get_saxo_catalog(asset_type: Optional[str] = None, q: Optional[str] = None,
     return [dict(r) for r in rows]
 
 
+def get_saxo_catalog_by_symbol(symbol: str) -> Optional[Dict[str, Any]]:
+    conn = get_conn()
+    row = conn.execute(
+        "SELECT * FROM saxo_instrument_catalog WHERE symbol = ? COLLATE NOCASE LIMIT 1", (symbol,)
+    ).fetchone()
+    conn.close()
+    return dict(row) if row else None
+
+
 def get_saxo_catalog_summary() -> List[Dict[str, Any]]:
     conn = get_conn()
     rows = conn.execute("""
diff --git a/backend/services/saxo_client.py b/backend/services/saxo_client.py
index 1eaf4bb..4fdb720 100644
--- a/backend/services/saxo_client.py
+++ b/backend/services/saxo_client.py
@@ -117,6 +117,20 @@ def resolve_instrument(symbol: str, asset_types: str = _OPTION_ASSET_TYPES) -> D
     if cache_key in _root_uic_cache:
         return _root_uic_cache[cache_key]
 
+    # Fast path: exchange-suffixed catalog symbols (e.g. "EUU:XCME", "OG:xcme") are Saxo
+    # identifiers, not natural-language search terms — Saxo's free-text Keywords search
+    # isn't reliable for them. If we already cached this exact symbol via a catalog
+    # refresh, use its known Uic directly instead of re-searching live.
+    from services.database import get_saxo_catalog_by_symbol
+    cached_entry = get_saxo_catalog_by_symbol(symbol)
+    if cached_entry:
+        result = {
+            "uic": cached_entry["uic"], "symbol": cached_entry["symbol"],
+            "description": cached_entry["description"], "asset_type": cached_entry["asset_type"],
+        }
+        _root_uic_cache[cache_key] = result
+        return result
+
     data = _get("/ref/v1/instruments", {"Keywords": symbol, "AssetTypes": asset_types})
     items = data.get("Data") or data.get("data") or []
     if not items:
diff --git a/frontend/src/pages/StrategyBuilder.tsx b/frontend/src/pages/StrategyBuilder.tsx
index 7af64c5..d43520b 100644
--- a/frontend/src/pages/StrategyBuilder.tsx
+++ b/frontend/src/pages/StrategyBuilder.tsx
@@ -584,7 +584,7 @@ export default function StrategyBuilder() {
     ...(saxoCatalog ?? []).map(c => c.symbol),
   ])).sort()
 
-  const { data: chain, isLoading: chainLoading, isError: chainError, refetch: refetchChain, isFetching } =
+  const { data: chain, isLoading: chainLoading, isError: chainError, error: chainErrorObj, refetch: refetchChain, isFetching } =
     useOptionChainSlice(symbol, horizonDays, 3)
 
   useEffect(() => {
@@ -680,7 +680,8 @@ export default function StrategyBuilder() {
 
       {chainError && (
         <div className="px-4 py-3 rounded border border-red-700/40 bg-red-900/10 text-xs text-red-300 flex items-center gap-2">
-          <AlertTriangle className="w-4 h-4" /> Chaîne d'options indisponible pour {symbol}. Essayez un autre symbole (ETF/action optionable).
+          <AlertTriangle className="w-4 h-4" />
+          {(chainErrorObj as any)?.response?.data?.detail ?? `Chaîne d'options indisponible pour ${symbol}. Essayez un autre symbole.`}
         </div>
       )}