Issue while trying to post / get an API on expo - react-native

Question

I'm new to react-native and it's my first app.
I'm trying to develop my app and connect it to my API. I develop all my app with the navigator view on Expo and there is no problem, the connection is good and I can get or post everything.
Now that I'm trying to fetch it with expo on my Android or Apple, there is no response.
Here is my code for the authentication:
login.js
import { post } from '../request/post';
export const login = (mail, pass) => {
console.log(mail)
console.log(pass)
console.log("POST request for login");
return post('/api/login', {
email: mail,
password: pass,
mobile: true
});
};
post.js
import { API_URL } from '../url';
import { getStorageToken } from '../../utils/asyncStorage';
const getHeaders = async () => {
const token = await getStorageToken();
const headers = {
Accept: 'application/json',
'Content-Type': 'application/json'
};
if (token !== 'undefined' && token.length > 0) {
headers['auth'] = `${token}`;
}
return headers;
};
export const post = async (destination, body) => {
const headers = await getHeaders();
const result = await fetch(`${API_URL}${destination}`, {
method: 'POST',
headers,
body: JSON.stringify(body),
});
console.log(result);
if (result.ok) {
return await result.json();
}
throw { error: result.status };
};
loginPage.js
import React from 'react';
import { View, Text, TouchableOpacity, StyleSheet, ScrollView, Image, TextInput, Linking } from 'react-native';
import { setStorageAfterConnection } from '../../utils/asyncStorage';
import { CheckBox, Icon } from 'react-native-elements';
import { login } from '../../api/auth/login';
export default class LogIn extends React.Component {
constructor(props) {
super(props);
this.state = {
email: '',
password: '',
errorMessage: ''
};
}
submit = () => {
login(this.state.email, this.state.password)
.then(async (res) => {
await setStorageAfterConnection(res);
this.props.navigation.navigate('Home');
})
.catch((res) => {
if (res && res.error) {
this.setState({ errorMessage: res.error});
}
this.setState({ errorMessage: "Erreur de connexion"});
});
};
render() {
return (
...............................................
);
}
}
I tried to debug it and it seems to not find the function post() because I don't have any network request. I do not know what's the correct way to do an "API" component so I think I probably made some mistakes but I didn't find what I'm missing.
I used Lan connection and my API isn't hosted on local.
Regards,

Answer 1

Try to add async-await to "login":
export const login = async (mail, pass) => { <---- 'async' ADDED
console.log(mail)
console.log(pass)
console.log("POST request for login");
return await post('/api/login', { <---- 'await' ADDED
email: mail,
password: pass,
mobile: true
});
};

Answer 2

I tried to put some debug on my code:
export const post = async (destination, body) => {
console.log("A");
const headers = await getHeaders();
console.log("B")
const result = await fetch(`${API_URL}${destination}`, {
method: 'POST',
headers,
body: JSON.stringify(body),
});
console.log(result);
if (result.ok) {
return await result.json();
}
throw { error: result.status };
};
And I get on the console:
email
password
POST request for login
A
So the problem seems to be on my await getHeaders()
EDIT: Problem was solved. It was because of the getHeaders that try to get the token and failed.