I placed some houses in my scene, but when i hit play their position on Y-axis changes automatically and they disappear from the scene!

these houses are downloaded from asset store ‘MedievelHouse’. How can i solve this issuse? all other things in my scene remains at their position.

Do the models have an animation component? Is ‘Play on Awake’ ticked? Untick Play on Awake, or disable/remove the animation component.