csrf session token missing flask

Question

I am trying to use csrf protection on my forms but I always get an error saying I am missing the csrf session token.

I dont know whats wrong with my code, maybe someone here can help me understand what I am doing wrong.

my code:

app = Flask(__name__)
csrf = CSRFProtect(app)

@app.route("/reserve", methods=["GET", "POST"])
def reserve():
   if request.method == "GET" :
       return render_template("reserve.html", csrf_token=generate_csrf())


<form id="Reserve" action="/reserve" method="post">
   <!-- csrf protection -->
   <input type="hidden" name="csrf_token" value="{{ csrf_token }}"/>
   <input type="text" placeholder="Name">
   <button type="submit">
        Submit
   </button>
</form>

I have tried using: <input type="hidden" name="csrf_token" value="{{ csrf_token() }}"/> but it still wont work.