WPSE335 Humidity always 15% too low

recently bought a BME280 (art.nr. WPSE335) sensor to measure the air condition. After setting up the sensor on my Raspberry Pi B+ via the I²C bus, I noticed that the humidity is always about 15% too low compared to two other hygrometers. Is this a known problem?

All the best

@lma ,

Maybe a sensor calibration can help:

See here how to: https://www.hackster.io/whitebank/humidity-sensor-calibration-3c5ace
or: Humidity Sensor Calibration - Arduino Project Hub

Here is code for RPi and BME280 with compensation formulas as in [datasheet] of “Bosch Sensortec” (https://www.velleman.eu/downloads/29/infosheets/bme280_datasheet.pdf)