При подключении к базе данных postgresql выдает ошибку sqlalchemy.exc.OperationalError

Пишу проект, и вот возникла не задача. Проблема в базе данных. Написал код для базы данных postgresql, используя sqlalchemy. Запускаю uvicorn main:app --reload, выходит такая ошибка:

sqlalchemy.exc.OperationalError: (psycopg2.OperationalError) could not connect to server: Connection refused
        Is the server running on host "localhost" (127.0.0.1) and accepting
        TCP/IP connections on port 5432?

(Background on this error at: https://sqlalche.me/e/20/e3q8)

Питон файлы: .env :

POSTGRES_USER=postgres
POSTGRES_PASSWORD=yourpassword
POSTGRES_SERVER=localhost
POSTGRES_PORT=5432
POSTGRES_DB=yourdbname_eg_debug

config.py:

import os
from dotenv import load_dotenv

from pathlib import Path
env_path = Path('.') / '.env'
load_dotenv(dotenv_path=env_path)

class Settings:
    PROJECT_NAME:str = "Job Board"
    PROJECT_VERSION: str = "1.0.0"

    POSTGRES_USER : str = os.getenv("POSTGRES_USER")
    POSTGRES_PASSWORD = os.getenv("POSTGRES_PASSWORD")
    POSTGRES_SERVER : str = os.getenv("POSTGRES_SERVER","localhost")
    POSTGRES_PORT : str = os.getenv("POSTGRES_PORT",5432) # default postgres port is 5432
    POSTGRES_DB : str = os.getenv("POSTGRES_DB","tdd")
    DATABASE_URL = f"postgresql://{POSTGRES_USER}:{POSTGRES_PASSWORD}@{POSTGRES_SERVER}:{POSTGRES_PORT}/{POSTGRES_DB}"

settings = Settings()

session.py :

from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker

from core.config import settings


SQLALCHEMY_DATABASE_URL = settings.DATABASE_URL
engine = create_engine(SQLALCHEMY_DATABASE_URL)

SessionLocal = sessionmaker(autocommit=False,autoflush=False,bind=engine)

base_class.py :

from typing import Any
from sqlalchemy.ext.declarative import as_declarative, declared_attr


@as_declarative()
class Base:
    id: Any
    __name__: str

    #to generate tablename from classname
    @declared_attr
    def __tablename__(cls) -> str:
        return cls.__name__.lower()

main.py:

from fastapi import FastAPI
from fastapi.staticfiles import StaticFiles
from core.config import settings
from apis.general_pages.route_homepage import general_pages_router
from db.session import engine   
from db.base_class import Base  


def include_router(app):
    app.include_router(general_pages_router)


def configure_static(app):
    app.mount("/static", StaticFiles(directory="static"), name="static")


def create_tables():           
    Base.metadata.create_all(bind=engine)

    
def start_application():
    app = FastAPI(title=settings.PROJECT_NAME,version=settings.PROJECT_VERSION)
    include_router(app)
    configure_static(app)
    create_tables()       
    return app

app = start_application()

requirements.txt:

fastapi
uvicorn

#for template  
jinja2 

#for static files
aiofiles

#for database   
sqlalchemy         
psycopg2

#for loading environment variables 
python-dotenv