why jinja2's function FileSystemLoader() doesn't work

Question

I'm following a tutorial about jinja2 library in real python, but every time I use a Filesystem Loader() function an error raise that say

Traceback (most recent call last):
  File "c:\Users\m00n\Desktop\jinja\write_messages.py", line 12, in <module>
    template = environment.get_template("message.txt")
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\m00n\AppData\Roaming\Python\Python312\site-packages\jinja2\environment.py", line 1010, in get_template
    return self._load_template(name, globals)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\m00n\AppData\Roaming\Python\Python312\site-packages\jinja2\environment.py", line 969, in _load_template
    template = self.loader.load(self, name, self.make_globals(globals))
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\m00n\AppData\Roaming\Python\Python312\site-packages\jinja2\loaders.py", line 125, in load    
    source, filename, uptodate = self.get_source(environment, name)
                                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "C:\Users\m00n\AppData\Roaming\Python\Python312\site-packages\jinja2\loaders.py", line 204, in get_source
    raise TemplateNotFound(template)
jinja2.exceptions.TemplateNotFound: message.txt

I thought that the problem was with python virtual environment so I try to exit it but it didn't work this is my python code

from jinja2 import Environment, FileSystemLoader

max_score = 100
test_name = "Python Challenge"
students = [
    {"name": "Sandrine",  "score": 100},
    {"name": "Gergeley", "score": 87},
    {"name": "Frieda", "score": 92},
]

environment = Environment(loader=FileSystemLoader("templates/"))
template = environment.get_template("message.txt")

for student in students:
    filename = f"message_{student['name'].lower()}.txt"
    content = template.render(
        student,
        max_score=max_score,
        test_name=test_name
    )
    with open(filename, mode="w", encoding="utf-8") as message:
        message.write(content)
        print(f"... wrote {filename}")

and this is the message.txt

{# templates/message.txt #}

Hello {{ name }}!

I'm happy to inform you that you did very well on today's {{ test_name }}.
You reached {{ score }} out of {{ max_score }} points.

See you tomorrow!
Anke