I am looking for a little help. Three stop DMC. Issue / Car is at lowest landing. Press up hall call doors open place a car call, car goes up about three inches and re-level's back down to landing. Then it will not take another call. Did a re-sink of the telescopic pistons and checked all piston sensors. They all seem to work. Ran car on inspection top to bottom it cleared the issue for a while. Same issue came back in two days. Unfortunately we do not have a World tool to look at the faults. Any Ideas?