It is likely that you have pressed the calibration button the scale and begun the process of calibrating the scale.
While scales we carry generally are pre-calibrated, they also give you the option of calibrating the scale yourself.
Once you begin calibration, though, you must complete it for the scale to function properly. If your scale is flashing
2000, then you will need to place 2000g of calibration weights on to the scale to calibrate it.