Why JSON.string is ommiting some values?

Question

console.log(saveState) //IT RETURNS {user: {lat: -20.8213224, lng: -49.3581463}}
console.log(typeof saveState) //RETURNS "object"
console.log(JSON.stringify(saveState)) //RETURNS {"user":{}}

Why is it happening, what i'm doing wrong? I'm using Javascript

This is the code of the error: I'm trying to take states from localStorage, and send it to redux Storage. I'm coding in Next.JS + Redux

Codes below

app.tsx

import type { AppProps } from 'next/app'
import { localStorageKeys, storeWrapper } from '../store'
import { Provider } from 'react-redux'
import { useEffect } from 'react'
import { userUpdate } from '../store/actions/users'
import GlobalStyle from '../styles/global'
import { Navbar } from '../components/Navbar'
import CategorySelector from '../components/CategorySelector'
import Head from 'next/head'

function App({ Component, pageProps }: AppProps) {
  const {store, props} = storeWrapper.useWrappedStore(pageProps)

  useEffect(()=>{
    let state: any = localStorage.getItem(process.env.NEXT_PUBLIC_STORAGE_KEY||"")
   
    if(state){
        try{
            state = JSON.parse(state)
            if(state.user){
              if(!state.user.lat || !state.user.lng){
                navigator.geolocation.getCurrentPosition((pos)=>{
                  state.user.lat = pos.coords.latitude;
                  state.user.lng = pos.coords.longitude;
                })
              }
            }
            else{
              navigator.geolocation.getCurrentPosition((pos)=>{
                state.user.lat = pos.coords.latitude;
                state.user.lng = pos.coords.longitude;
              })
            }
            
        }catch{
            state = {}
        }
    }else{
        state = {}

        state.user = {}
        
        navigator.geolocation.getCurrentPosition((pos)=>{
          state.user.lat = pos.coords.latitude,
          state.user.lng = pos.coords.longitude
        })
    }

    Object.entries(localStorageKeys).map((val, index)=>{
      const [ref, key] = val
      if(state[ref]){
        switch(ref){
          case 'user':
            store.dispatch(userUpdate(state[key]))
            break
          default:
            break
        }
      }
    })
  })

  return (
    <Provider store={store}>
      <GlobalStyle />
      <Navbar />
      <CategorySelector />
      <Component {...pageProps} />
    </Provider>
  )
}

export default App

Here is the function that isn't working well, when I'm trying to convert the state to string to save, it returns nothing, but when it is in object type, it returns lat and lng properly saveState.ts

export const saveState = (key: string, value: any) => {
    let state: any = localStorage.getItem(keyName)
    console.log("SAVE", key, value)
    if(state){
        try{
            state = JSON.parse(state)
        }catch{
            state = {}
        }
    }else{
        state = {}
    }

    state[key] = value

    const saveState = state

    console.log(saveState)
    console.log(typeof saveState)
    console.log(JSON.stringify({saveState}))
    
    localStorage.setItem(keyName, JSON.stringify(state))
}

I really dont know what to do