Error: sqlalchemy.exc.StatementError: (sqlalchemy.exc.InvalidRequestError) A value is required for bind parameter 'user_name'

I have a Flask project that interacts with MySQL DB through Flask-SQLAlchemy Core.

I’m getting an error while binding parameters to sql query.

In this I want to bind dynamic parameters fetched from POSTMAN and return query for that specific data present in DB.

e.g:- Suppose from POSTMAN I’ve received user_name = ‘Pratik’ password = ‘123456’

SQL query to be implemented:- SELECT id, user_name, password, email_address, dob, uid FROM user WHERE user_name = ‘Pratik’ and password = ‘123456’

NOTE: I’ve hashed my password at the time of creation.

@app.route('/login', methods=['POST'])
def login():
    
    auth= user_schema.load(request.get_json())   #Data validated and fetched from postman
    user_name=auth['user_name']    #Data fetched from POSTMAN
    password=generate_password_hash(auth['password'], method = 'sha256')    # Data fetched from POSTMAN
    
    conn = engine.connect()
    results = conn.execute(text(f"SELECT id, user_name, password, email_address, dob, uid FROM user WHERE user_name = :user_name and password = :password",{"user_name": user_name, "password": password}))

    result_dict = [dict(u) for u in results.fetchall()]
    print (result_dict)
    return "response"