Dynamic height adjustment of 3d Tiles

Hi, I have generated Cesium 3D tiles from OBJ file in contextcapture tool. when i tried to place them on cesium world terrain, some placed on ground, some underground and others flying on ground. how can i adjust the height of 3d Tiles dynamically and make clamp to ground.
I tried height adjustment manually for one object but i have several objects which face height issues. (Cesium Sandcastle )

objects(data) that I’m working spread across multiple countries.
i checked this below link, kind of similar problem that YingcaiDong solved. but didnt post the solution to it.
3D-tiles style: heightOffset don't change the tiles' elevation · Issue #291 · CesiumGS/3d-tiles · GitHub .

also, In comparison to cesium 3D tiles format, which other formats are best to use in terms of memory usage and authentic display in cesium js

can anyone show solution please