Unfortunately worked 12 months only

I can install the pump station of a sanitary operation and connected a sink and washing machine (drain hose hangs in the cup sinks) The plant was 11 months perfectly, then the laundry room was suddenly underwater. The installer has the system expanded but found no errors. Then it ran back again stand for 6 weeks to the laundry room underwater. The installer typed on the pressure switch and the foam may occur. Somehow this seems to make problems. The system then ran again but I have to be replaced by another. For my purposes, waste water from the washing machine and sink to pump 2mtr high, completely unsuitable.