Dover composite bouncing up and down

Hi all, I got a dover composite that everytime it reaches the floor instead of stoping at the floor it starts leveling up and down this is happens on both directions. If i hold the LUD relay for 1/2 a sec. It will stop perfectly at the floor. Also if the car is at the 2nd floor or any floor and I give it a down hall call from the 4th floor it will arrive to floor with no problems but if I give it a up hall call it won't stop and starts doing the up and down thing and same thing happens if i do the same thing if the car is above the hall call.
Any help will be appreciated...

MOP, UA and DA must be off at the time of LUD in

Thanks for the tip... my UA and DA are not droping. They drop if the car is running up for a down call then UA drops but not if is a up or car call. If it is goind down for an up call then DA drops but not for and down or car call...

Found the problem, turn out to be bad contacts on relays DR1 AND DR2 they feed the UA and DA relays.
Thanks for the tip NOTIME