How to get JSON.parser value after save to AsyncStorage using Json.stringfy in react native?

I want to use the data from JSON.stringify that I save locally from async storage, so I can manage them locally (like user data for login)

I already save it to AsyncStorage

componentDidMount = async () => {
      fetch('My_url', {
         method: 'GET'
      })
      .then((response) => response.json())
      .then((responseJson) => {
         console.log(responseJson);
         this.setState({
            data: responseJson
         })
      })
      .catch((error) => {
         console.error(error);
      });

   }

   saveData = async () => {
     try {
                await AsyncStorage.setItem('user', JSON.stringify(this.state.data));
                Alert.alert('Saved', 'Successful');
            } catch (error) {
                Alert.alert('Error', 'There was an error.')
            }

this is the JSON

0   
username    "admin2"
password    "*****"
access  "1"
name    "dwi"
phone_number    "087613721"
email   "**@****.com"
score   null
status  "0"
1   
username    "admin3"
password    "***"
access  "1"
name    "Satria"
phone_number    "****"
email   "*****3@*****.com"
score   null
status  "0"

and I try to get the value using this, but can't show anything in node console.log, it said "unidentified" (i just using press button on this)

displayData = async ()=>{
    try{
      let user = await AsyncStorage.getItem('user');
      let parsed = JSON.parse(user);
      console.log(parsed.email);
    }
    catch(error){
      alert(error)
    }
  }

can some JSON parser output use like to be database function? like for login so we can log in and check the data user from json.parser that I store in the data using async storage? or output some data that we want to be used like in where statement in the SQL ?