AWS에 업로드하고 고정IP로 접속한 다음

회원가입 후 질문을 등록하려고 하면 다음과 같은 에러가 나옵니다. 왜 그런 겁니까?

sqlalchemy.exc.IntegrityError
sqlalchemy.exc.IntegrityError: (sqlite3.IntegrityError) NOT NULL constraint failed: question.user_id
[SQL: INSERT INTO question (subject, content, create_date, user_id) VALUES (?, ?, ?, ?)]
[parameters: ('테스트', '테스트', '2022-03-27 23:37:28.493589', None)]
(Background on this error at: https://sqlalche.me/e/14/gkpj)

Traceback (most recent call last)
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/engine/base.py", line 1808, in _execute_context
self.dialect.do_execute(
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/engine/default.py", line 732, in do_execute
cursor.execute(statement, parameters)
The above exception was the direct cause of the following exception:
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/flask/app.py", line 2091, in call
return self.wsgi_app(environ, start_response)
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/flask/app.py", line 2076, in wsgi_app
response = self.handle_exception(e)
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/flask/app.py", line 2073, in wsgi_app
response = self.full_dispatch_request()
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/flask/app.py", line 1518, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/flask/app.py", line 1516, in full_dispatch_request
rv = self.dispatch_request()
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/flask/app.py", line 1502, in dispatch_request
return self.ensure_sync(self.view_functions[rule.endpoint])(req.view_args)
File "/home/ubuntu/projects/myproject/pybo/views/auth_views.py", line 65, in wrapped_view
return view(kwargs)
File "/home/ubuntu/projects/myproject/pybo/views/question_views.py", line 36, in create
db.session.commit()
File "", line 2, in commit

File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/orm/session.py", line 1431, in commit
self.transaction.commit(_to_root=self.future)
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/orm/session.py", line 829, in commit
self._prepare_impl()
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/orm/session.py", line 808, in _prepare_impl
self.session.flush()
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/orm/session.py", line 3363, in flush
self._flush(objects)
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/orm/session.py", line 3503, in _flush
transaction.rollback(_capture_exception=True)
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/util/langhelpers.py", line 70, in exit
compat.raise(
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/util/compat.py", line 207, in raise_
raise exception
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/orm/session.py", line 3463, in flush
flush_context.execute()
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/orm/unitofwork.py", line 456, in execute
rec.execute(self)
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/orm/unitofwork.py", line 630, in execute
util.preloaded.orm_persistence.save_obj(
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/orm/persistence.py", line 244, in save_obj
_emit_insert_statements(
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/orm/persistence.py", line 1237, in _emit_insert_statements
result = connection._execute_20(
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/engine/base.py", line 1620, in _execute_20
return meth(self, args_10style, kwargs_10style, execution_options)
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/sql/elements.py", line 325, in _execute_on_connection
return connection._execute_clauseelement(
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/engine/base.py", line 1487, in _execute_clauseelement
ret = self._execute_context(
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/engine/base.py", line 1851, in _execute_context
self._handle_dbapi_exception(
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/engine/base.py", line 2032, in _handle_dbapi_exception
util.raise(
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/util/compat.py", line 207, in raise_
raise exception
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/engine/base.py", line 1808, in _execute_context
self.dialect.do_execute(
File "/home/ubuntu/venvs/myproject/lib/python3.8/site-packages/sqlalchemy/engine/default.py", line 732, in do_execute
cursor.execute(statement, parameters)
sqlalchemy.exc.IntegrityError: (sqlite3.IntegrityError) NOT NULL constraint failed: question.user_id
[SQL: INSERT INTO question (subject, content, create_date, user_id) VALUES (?, ?, ?, ?)]
[parameters: ('테스트', '테스트', '2022-03-27 23:37:28.493589', None)]
(Background on this error at: https://sqlalche.me/e/14/gkpj)
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