Rain Soft Filter under neither sink

I get this alarm that comes up to change the drinking the drinking filter that's under the sink. I changed the filter and tried to reset the alarm. I looked in the manual but there is no instruction on how to do so. In the past my parents would call the service person to come and reset it. They would charge him 90$ for the call. He would ask them how to reset it and wouldn't tell him. So he would have to call every time he needed the filter changed. Does anyone know how get rid of the alarm