[에러노트] Uncaught Error: The slice reducer for key ~ returned undefined during initialization.

1. 문제점

Uncaught Error: The slice reducer for key "DetailTodo" returned undefined during initialization. If the state passed to the reducer is undefined, you must explicitly return the initial state. The initial state may not be undefined. If you don't want to set a value for this reducer, you can use null instead of undefined.

2. 해결방법

모듈코드에서 default값 넣어주기

default:
      return state;
      

참고 사이트