diff --git a/lib/contract-resolver.ts b/lib/contract-resolver.ts
index df6986d..e82e259 100644
--- a/lib/contract-resolver.ts
+++ b/lib/contract-resolver.ts
@@ -37,8 +37,13 @@ const PROBE_WINDOW = 6;
 // route handlers (settings page, manual trades) never see.
 const _g = globalThis as typeof globalThis & {
     __contractCache?: Map<string, { contract: ResolvedContract; resolvedAt: number }>;
+    __contractRoots?: Map<string, string>;
 };
 const cache = (_g.__contractCache ??= new Map());
+/** Contract id → the root it was resolved for. Unlike the cache it never
+ *  expires: a position opened hours ago still needs its instrument's name
+ *  (lib/trade-mix.ts). Front months are few, so it stays small. */
+const roots = (_g.__contractRoots ??= new Map());
 const CACHE_TTL_MS = 30 * 60 * 1000; // 30 minutes
 
 export function getCachedContract(symbol: string): ResolvedContract | null {
@@ -51,6 +56,12 @@ export function getCachedContract(symbol: string): ResolvedContract | null {
     return entry.contract;
 }
 
+/** The root a resolved contract id belongs to, however long ago it was
+ *  resolved; null for one this process never resolved. */
+export function rootOfContract(contractId: number | string): string | null {
+    return roots.get(String(contractId)) ?? null;
+}
+
 export function getAllCachedContracts(): Record<string, ResolvedContract | null> {
     const result: Record<string, ResolvedContract | null> = {};
     for (const [symbol, entry] of cache) {
@@ -205,6 +216,7 @@ export async function resolveContracts(
             };
             results[sym] = contract;
             cache.set(sym, { contract, resolvedAt: Date.now() });
+            roots.set(String(contract.id), sym);
 
             if (rolledFrom) {
                 console.log(`[contract-resolver] ${sym}: ${rolledFrom} → ${match.name} ROLLED (by volume)`);
diff --git a/lib/trade-mix.ts b/lib/trade-mix.ts
index 71e17ff..96191fc 100644
--- a/lib/trade-mix.ts
+++ b/lib/trade-mix.ts
@@ -5,14 +5,15 @@
  * Open positions come off the client's position map, each contract named by
  * the instrument it is: a DXtrade position carries its symbol; a futures one
  * is looked up among the contracts this machine has entered (recorded at the
- * fill, kept across restarts), then the resolver's cache and TopstepX's own.
+ * fill, kept across restarts), TopstepX's own, and every contract the
+ * resolver has resolved in this process (never expiring).
  * Entries are counted as they fill and kept in a setting per trade date, so
  * a restart doesn't lose the day.
  */
 
 import { getSetting, setSetting } from './db';
 import { currentTradeDateCT } from './trading-logic';
-import { getAllCachedContracts } from './contract-resolver';
+import { rootOfContract } from './contract-resolver';
 import { errorMessage } from './platform-client';
 import type { InstrumentCount, TradeMix } from './master-protocol';
 
@@ -71,16 +72,15 @@ export function tradeMixFor(
     // eslint-disable-next-line @typescript-eslint/no-explicit-any
     client: any,
 ): TradeMix {
+    // Recorded at the fill, then TopstepX's own contracts, then every
+    // contract this process resolved (Tradovate's, however long ago).
     const names = new Map<string, string>();
-    for (const [root, contract] of Object.entries(getAllCachedContracts())) {
-        if (contract) names.set(String(contract.id), root);
-    }
     const own = typeof client.contractRoots === 'function' ? (client.contractRoots() as Map<string, string>) : null;
     for (const [id, root] of own ?? []) names.set(id, root);
     for (const [id, instrument] of Object.entries(readJson<Record<string, string>>(NAMES_KEY) ?? {})) names.set(id, instrument);
     const instrumentOf = (contractId: unknown): string => (firm.platform === 'dxtrade'
         ? String(contractId).split('|')[0]
-        : names.get(String(contractId)) ?? `#${String(contractId)}`);
+        : names.get(String(contractId)) ?? rootOfContract(contractId as number | string) ?? `#${String(contractId)}`);
 
     const open = new Map<string, InstrumentCount>();
     for (const acc of (client.accountList ?? []) as { id: number }[]) {