diff --git a/app/app.py b/app/app.py
index b151ddb..f028f24 100644
--- a/app/app.py
+++ b/app/app.py
@@ -395,29 +395,31 @@ google = oauth.register(
     client_kwargs={"scope": "openid email profile"},
 )
 
+
 def login_required(f):
     @wraps(f)
     def wrapper(*args, **kwargs):
-        # If using OAuth
-        if app.config["AUTH_MODE"] == "oauth":
-            if "user" not in session:
-                return redirect(url_for("login"))
-            return f(*args, **kwargs)
-
-        # If using DB authentication
-        if "db_user" not in session:
+        key = "user" if app.config["AUTH_MODE"] == "oauth" else "db_user"
+        if key not in session:
             return redirect("/auth/login")
-        
-        email = session["db_user"]["email"]
+
+        email = session[key]["email"]
+        db = SessionLocal()
         u = db.query(User).filter_by(email=email).first()
+        db.close()
+
         if not u:
-            session.pop("db_user", None)
+            session.pop(key, None)
             return redirect("/auth/login")
 
         return f(*args, **kwargs)
     return wrapper
 
 
+
+
+
+
 @app.route("/auth/login", methods=["GET", "POST"])
 def db_login():
     if request.method == "GET":
@@ -655,7 +657,10 @@ def promote(email):
 @admin_required
 def admin_conversations(email):
     db = SessionLocal()
+    email = session["user"]["email"] if app.config["AUTH_MODE"] == "oauth" else session["db_user"]["email"]
     convs = db.query(Conversation).filter_by(user_email=email).all()
+    if not convs:
+        return jsonify({"erro": "Conversas não encontradas."}), 404
     data = [{"id": c.id, "title": c.title, "tags": c.tags} for c in convs]
     db.close()
     return jsonify(data)
@@ -689,7 +694,16 @@ def chat_stream():
     cid = request.args.get("conversation_id")
 
     db = SessionLocal()
-    msgs = db.query(Message).filter_by(conversation_id=cid).order_by(Message.created_at).all()
+    email = session["user"]["email"] if app.config["AUTH_MODE"] == "oauth" else session["db_user"]["email"]
+    msgs = (
+        db.query(Message)
+        .join(Conversation, Message.conversation_id == Conversation.id)
+        .filter(Conversation.id == cid, Conversation.user_email == email)
+        .order_by(Message.created_at)
+        .all()
+    )
+
+    
     db.close()
 
     chatml = [{"role": m.role, "content": m.content} for m in msgs]
@@ -741,7 +755,11 @@ def list_conversations():
 @rate_limited
 def export_md(cid):
     db = SessionLocal()
+    email = session["user"]["email"] if app.config["AUTH_MODE"] == "oauth" else session["db_user"]["email"]
     conv = db.query(Conversation).filter_by(id=cid, user_email=email).first()
+    if not conv:
+        return jsonify({"erro": "Conversa não encontrada."}), 404
+
     msgs = conv.messages
 
     md = f"# {conv.title}\n\n"
@@ -804,7 +822,10 @@ def import_file(cid):
 @rate_limited
 def export_pdf(cid):
     db = SessionLocal()
+    email = session["user"]["email"] if app.config["AUTH_MODE"] == "oauth" else session["db_user"]["email"]
     conv = db.query(Conversation).filter_by(id=cid, user_email=email).first()
+    if not conv:
+        return jsonify({"erro": "Conversa não encontrada."}), 404
     msgs = conv.messages
 
     html = "<h1>{}</h1>".format(conv.title)
@@ -936,7 +957,11 @@ def stream():
 def share(cid):
     target_email = request.json.get("email")
     db = SessionLocal()
+    email = session["user"]["email"] if app.config["AUTH_MODE"] == "oauth" else session["db_user"]["email"]
     conv = db.query(Conversation).filter_by(id=cid, user_email=email).first()
+    if not conv:
+        return jsonify({"erro": "Conversa não encontrada."}), 404
+    
     conv.shared = target_email
     db.commit()
     db.close()
@@ -949,7 +974,11 @@ def share(cid):
 def update_tags(cid):
     tags = request.json.get("tags", [])
     db = SessionLocal()
+    email = session["user"]["email"] if app.config["AUTH_MODE"] == "oauth" else session["db_user"]["email"]
     conv = db.query(Conversation).filter_by(id=cid, user_email=email).first()
+    if not conv:
+        return jsonify({"erro": "Conversa não encontrada."}), 404
+    
     conv.tags = ",".join(tags)
     db.commit()
     db.close()
@@ -962,10 +991,8 @@ def update_tags(cid):
 def search():
     q = request.args.get("q", "").lower()
     user_email = session["user"]["email"]
-
     db = SessionLocal()
     convs = db.query(Conversation).filter_by(user_email=user_email).all()
-
     results = []
     for c in convs:
         for m in c.messages:
@@ -977,8 +1004,7 @@ def search():
                     "content": m.content,
                     "created_at": m.created_at.isoformat()
                 })
-
-    db.close()
+   db.close()
     return jsonify(results)
 
 from pywhispercpp.model import Model