React native How to get only one part of my JSON back to Axios API

[beginner in React Native] I am working on the authentification. I have my call to API. It sends me back a JSON object with all the infos login which is inside a string called "j".
How can I get only the the object inside the j and transform it into an object to use in my app?
thank you for your help !

import { createSlice, createAsyncThunk } from "@reduxjs/toolkit";
import axios from "axios";
import base64 from "react-native-base64";

export const loginUser = createAsyncThunk(
  'users/login',
  async ({ codeClient, userEmail, password }, thunkAPI) => {
    try 
      {
          const response = await axios(
            {
              method: "post",
              url: "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX",
              params: 
                  {
      
                    AApplicationKey: "XXXXXXXXXXXXXXXXX",
                    AUriosCustomerID: "XXXXXXX",
                    AUserEmail: "XXXXXXXXXX",
                    AUserPwd: "XXXXXXXXX",
                  },
              headers: 
                  {
                    Authorization:
                      "Basic " +
                      base64.encode("xxxxxx" + ":" + "xxxxxxxxxxxxxxx"),
                    "Content-Type": "application/x-www-form-urlencoded",
                    Accept: "application/json",
                  }
            }
          );
          return JSON.parse(data.value[0].j);

      } catch (e) 
        {
          console.log('Error', e.response.data);
          return thunkAPI.rejectWithValue(e.response.data);
        }
  }
);```

>Solution :

In your code, the "const response" isn’t used.. you return "JSON.parse(data.value[0].j);"
So it can’t work.

Anyway your question is uncomplete without JSON answer is hard to say ^^

You should try

return JSON.parse(response.data.value[0].j);