diff --git a/src/lib/server/database.ts b/src/lib/server/database.ts
index b648d95c8f1..f582ada06d2 100644
--- a/src/lib/server/database.ts
+++ b/src/lib/server/database.ts
@@ -70,6 +70,8 @@ client.on("open", () => {
 	settings.createIndex({ assistants: 1 }).catch(console.error);
 	users.createIndex({ hfUserId: 1 }, { unique: true }).catch(console.error);
 	users.createIndex({ sessionId: 1 }, { unique: true, sparse: true }).catch(console.error);
+	// No unicity because due to renames & outdated info from oauth provider, there may be the same username on different users
+	users.createIndex({ username: 1 }).catch(console.error);
 	messageEvents.createIndex({ createdAt: 1 }, { expireAfterSeconds: 60 }).catch(console.error);
 	sessions.createIndex({ expiresAt: 1 }, { expireAfterSeconds: 0 }).catch(console.error);
 	sessions.createIndex({ sessionId: 1 }, { unique: true }).catch(console.error);
diff --git a/src/routes/assistants/+page.server.ts b/src/routes/assistants/+page.server.ts
index 7e190e25579..7d31f1f2cad 100644
--- a/src/routes/assistants/+page.server.ts
+++ b/src/routes/assistants/+page.server.ts
@@ -26,7 +26,7 @@ export const load = async ({ url, locals }) => {
 
 	// fetch the top assistants sorted by user count from biggest to smallest, filter out all assistants with only 1 users. filter by model too if modelId is provided
 	const filter: Filter<Assistant> = {
-		modelId: modelId ?? { $exists: true },
+		...(modelId && { modelId }),
 		...(!createdByCurrentUser && { userCount: { $gt: 1 } }),
 		...(createdByName ? { createdByName } : { featured: true }),
 	};