Can't pass lat, lng to weatherbit API, ReferenceError: data is not defined

I'm really struggling with my final project for my first ever coding course. Situation:

I'm able to successfully retrieve data from Geonames API, that looks like this:

Geonames API response:  {
  lat: '50.08804',
  lng: '14.42076',
  city: 'Prague',
  country: 'Czechia'
}

Now I need to pass the lat, lng values onto the next fuction, getWeatherData:

app.get('/weather', getWeatherData);

async function getWeatherData(req, res) {
    try {
        const { lat, lng } = req.query; // Extract lat and lng from the request query
        console.log(`Following geo data are being passed to Weatherbit: Lat: ${lat}, Lng: ${lng}`);

        const result = await getWeatherbitData(lat, lng); // Pass lat and lng to getWeatherbitData
        console.log('Weatherbit API response:', result);

        res.send(result);
    } catch (error) {
        console.log('Error in getWeatherData:', error);
        res.send(error);
    }
}

and I keep getting the error message "error in getWeatherData(lat, lng): ReferenceError: data is not defined" that points to the line

    const { lat, lng } = req.query; // Extract lat and lng from the request query

I can't figure out why is this happening, or what other way can I declare these values.

I searched on multiple forums and tried different formats of declaring, adjusting the client-side code, but always getting the same error. I'd greatly appreciate any hints on what might be going wrong. [here] project repository for reference