DHT11 is giving an error

my dht11 sensor has bin configured correctly but is not working?
it gives a msg value of
_msgid: "5e01a3d1.dfba7c"
topic: "rpi-dht11"
payload: "0.00"
humidity: "0.00"
isValid: false
errors: 4
sensorid: "dht11"
please help me?
what should i do?

Check that the sensor is working outside of Node-RED

DHT11's do regularly fail to read. The can also fail to return a reading if you try to do it too quickly.

They are also pretty terrible. They are very inaccurate and drift off even worse over time. The DHT22's are slightly but not much better. Sensors like the BME280 and the HTU21D can be had for pretty much the same price now and are far more accurate. They also use the I2C interface which makes them dead easy to use.