Docker-compose creates two containers but only runs one

Question

I'm trying to deploy a Flask app in a container and a MongoDB instance in an other container , but I'm having a problem with my Dockerfile / docker-compose.yml file. When i run docker-compose up -d, both containers are created but only one of them ends up running after this command line.

(flaskenv) C:\Users\LMartin\Zoov_Flask_App>docker-compose up -d
[+] Running 2/2
 - Container zoov_mongodb                Started                                                                                                 1.1s
 - Container zoov_flask_app-flaskapp1-1  Started                                                                                                 2.9s

(flaskenv) C:\Users\LMartin\Zoov_Flask_App>docker ps -a
CONTAINER ID   IMAGE                COMMAND                  CREATED        STATUS                     PORTS       NAMES
8e3012f3f3d6   testdocker2:latest   "python3"                15 hours ago   Exited (0) 5 seconds ago               zoov_flask_app-flaskapp1-1
3dca04bda58c   mongo:latest         "docker-entrypoint.s…"   15 hours ago   Up 6 seconds               27017/tcp   zoov_mongodb
0717f357e2d6   alpine/git           "git clone https://g…"   3 days ago     Exited (0) 3 days ago                  repo

As you can see, my flask container is created but not ran when I use docker compose, whereas everything seems to be working fine for the MongoDB container.
I think there is a problem in my Dockerfile, especially in my CMD statement at the end of it, but I can't figure out what I'm doing wrong.
Dockerfile:

FROM python:3.8-slim-buster

WORKDIR /app1/app

COPY ../../requirements.txt ../../requirements.txt
RUN pip install -r ../requirements.txt

COPY .. .
CMD ["python", "app1/app/run.py"]

I've tried several commands for this last line, such as CMD ["python", "-m", "flask", "run", "--host=0.0.0.0", "--port=8081"], or to switch the CMD with a RUN statement but nothing seems to be working.
Here is the docker-compose.yml file

version: "3.8"
services:
 mongodb:
  image: mongo:latest
  container_name: zoov_mongodb
  restart: unless-stopped
  command: mongod --auth
  environment:
   MONGO_INITDB_ROOT_USERNAME: zoovroot
   MONGO_INITDB_ROOT_PASSWORD: zoovrootpwd
   MONGODB_INITDB_DATABASE: zoovdb
   MONGODB_DATA_DIR: mongodb/database
   MONGODB_LOG_DIR: mongodb/logs
  volumes:
   - mongodbdata:/data/db
  networks:
   - backend

 flaskapp1:
  build:
   context: app1
   dockerfile: Dockerfile
  image: testdocker2:latest
  environment:
   APP_DEBUG: True
   APP_PORT: 8081
   MONGODB_DATABASE: zoovdb
   MONGODB_USERNAME: zoovuser
   MONGODB_PASSWORD: lucas123
   MONGODB_HOSTNAME: mongodb
  volumes:
   - appdata:/var/www
  depends_on:
   - mongodb
  networks:
   - frontend
   - backend

volumes:
 mongodbdata:
  driver: local
 appdata:
  driver: local

networks:
 frontend:
  driver: bridge
 backend:
  driver: bridge

What's wrong with what I did ?
Here is how my project folder looks like

Edit: Python code

from flask import Flask, render_template, jsonify, request, url_for, redirect
from flask_pymongo import PyMongo
import json
import os

app = Flask(__name__, template_folder="../templates")

@app.route('/')
def home():
    return render_template("home.html")

@app.route('/get', methods=['GET', 'POST'])
def selectbike():
    if request.method == "POST":
        b = request.form["nm"]
        return redirect(url_for("get_bike", id=b))
    else:
        return render_template("get.html")

@app.route('/get/<id>')
def get_bike(id):
    return id

@app.route('/all')
def get_all_bikes():
    return "allbikes"

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=8081, debug=True)

Edit 2 :

(flaskenv) C:\Users\LMartin\Zoov_Flask_App>docker-compose up -d
[+] Running 2/2
 - Container zoov_mongodb                Started                                                                                                 1.4s
 - Container zoov_flask_app-flaskapp1-1  Started                                                                                                 3.1s

(flaskenv) C:\Users\LMartin\Zoov_Flask_App>docker logs zoov_flask_app-flaskapp1-1

(flaskenv) C:\Users\LMartin\Zoov_Flask_App>