I am so frustrated currently. I've simplified this as much as possible to see what I am doing wrong and nothing works. Even completely isolated into it's own component it sends a blank object. Whether it is a const variable = async() => {} or async function name(){} syntax they both send blank objects. Here's my code:

​

import { StyleSheet, View, Text, TouchableOpacity } from "react-native";
import ROUTES from "../../constants/Routes";


export default function DebugScreen() {

    // const testing = async (e) => {
    //     console.log('in testing')
    //     const item = {
    //         userName: "dave"
    //     }

    //     const res = await fetch(ROUTES.ANDROID_USER_USERINFO, {
    //         method: 'POST',
    //         header: { 'Content-Type': 'application/json' },
    //         body: JSON.stringify(item)
    //     })
    //     const data = await res.json()
    //     console.log(data)

    // }

    async function testing() {
        console.log('in testing')
        const res = await fetch(ROUTES.ANDROID_USER_USERINFO, {
            method: 'POST',
            mode: 'cors',
            header: { 'Content-Type': 'application/json' },
            body: JSON.stringify({ userName: "dave" })
        })
        const data = await res.json()
        console.log(data)

    }

    return (
        <View style={styles.container}>
            <Text>Debug Stub</Text>
            <TouchableOpacity onPress={() => testing()}>
                <Text>Click Here To Send Info To Server</Text>
            </TouchableOpacity>
        </View>
    );
}

const styles = StyleSheet.create({
    container: {
        flex: 1,
        alignItems: 'center',
        justifyContent: 'center',
        backgroundColor: 'lightblue'
    }
})

I know the route is right cause it does update the json file via json-server I have set up. But it always updates it with a blank object. I also always get back a 201 reponse code. Every stack overflow post on this just says to make sure to not have 'mode': 'no-cors' which doesn't apply to me. I've seen another parameter in the header object about something like accept type, but even with that it still sends a blank object. I can't progress on this app until I figure this out so any help would be greatly appreciated