Here are common causes and solutions: (1) Your scale was not placed on a flat and hard surface. Please place your scale on a flat and hard floor. Avoid carpets and rugs. (2) The scale did not properly reset. It has a residual number. You need to perform another power-on reset. Push the active button(next to the charging port), IMMEDIATELY place the scale on a flat hard surface. Make sure the scale displays “0.0”, and then close the battery cover. (3) The scale was not calibrated when weighing. For each measurement, after turn the scale on, you need to wait “CAL” back to “0.0” before you step to take your measurement. (4) Getting off your scale too soon may lead to inaccurate readings. Please stay on the scale until your weight number is stable.