我正在学习redux。我试图通过递增递减值来学习redux。我写了一个代码。当我调度INCREMENT_BY_VALUE时，它显示NaN，但INCREMENT，DECREMENT和RESET工作正常。
下面是我的代码：

const { createStore } = require("redux")

const INCREMENT = 'INCREMENT'
const DECREMENT = 'DECREMENT'
const RESET = 'RESET'
const INCREMENT_BY_VALUE = "INCREMENT_BY_VALUE"

const initialCounterState = {
  count: 0
}

const incrementCounter = () => {
  return {
    type: INCREMENT
  }
}

const decrementCounter = () => {
  return {
    type: DECREMENT
  }
}

const incrementByValue = (value) => {
  return {
    type: INCREMENT_BY_VALUE,
    action: value
  }
}

const resetCounter = () => {
  return {
    type: RESET
  }
}

const counterReducer = (state = initialCounterState, action) => {
  switch (action.type) {
    case INCREMENT:
      return {
        ...state,
        count: state.count + 1
      }

    case DECREMENT:
      return {
        ...state,
        count: state.count - 1
      }

      
    case RESET:
      return {
        ...state,
        count: 0
      }

    case INCREMENT_BY_VALUE:
      return {
        ...state,
        count: state.count + action.payload
      }

    default:
      break;
  }
}

const store = createStore(counterReducer)

store.subscribe(() => {
  console.log(store.getState());
})

store.dispatch(incrementCounter())
store.dispatch(decrementCounter())
store.dispatch(resetCounter())
store.dispatch(incrementByValue(10))

我从我的代码中得到以下输出：

{ count: 1 }
{ count: 0 }
{ count: 0 }
{ count: NaN }

为什么会发生这种情况，我该如何解决？