Send float using json

I am trying to send a number with a comma through JSON to save them in a MySQL database through a api rest created in node js.

Endpoint code

router.post('/', (req, res) => {
    const sensorData = {
        id: null,
        temperatura: req.body.temperatura,
        humedad: req.body.humedad,
        indice_calor: req.body.indice_calor,
        fecha: null,
    };

Sensor.insertMetric(sensorData, (err, data) => {
    if(data && data.insertId){
        res.status(200).json({ 
            success: true,
            data: data
        });
    } else{
        res.status(500).json({
            success: false
        });
    }
});

JSON that sent

{
    "temperatura": 2.3,
    "humedad": 2.3,
    "indice_calor": 2.3
}

However, in the database the values are stored as 0.99