fetch(api.SEARCH_THE_ACCOUNT_ENDPOINT + "username=" + this.state.email, {
    method: 'GET',
    headers: {
        'access_token': access_token
    },
    // body: formBody
}).then((response) => {
    if (response.status >= 200 && response.status < 300) {
        return response.json();
    } else {
        return Promise.reject({ status: response.status, body: response.body });
    }
}).then((responseJson) => {
    console.log("Fetch Response");
    console.log(responseJson);
}).catch((error) => {
    // error = { status: response.status, body: response.body }
    if (error.status === 400 && error.body.status === 'TooManyPunch') {
        // do something
    } else if (error.status === 400 && error.body.status === 'UsernameFormatError') {
        // do something
    } else {
        console.log('I also dont know what is this going on :(');
    }
});

//--------------------------------------

fetch(api.SEARCH_THE_ACCOUNT_ENDPOINT + "username=" + this.state.email, {
    method: 'GET',
    headers: {
        'access_token': access_token
    },
    // body: formBody
}).then((response) => {
    if (response.status === 500) {
        return Promise.reject(500);
    } else {
        return response.json().then(responseJson => {
            return { status: response.status, json: responseJson };
        });
    }
}).then((response) => {
    // response.status, response.json
    if (response.status === 400 && response.json.status === 'TooManyPunch') {
        // do something
    } else if (response.status === 400 && response.json.status === 'UsernameFormatError') {
        // do something
    } else { // = status 2XX
        // do normal thing
    }
}).catch((error) => {
    if (error === 500) {
        // 500 Error Handling
    } else {
        // Unknown Error Handling, e.g. response.json() failed
    }
});