Objects fall through landscape after being packaged into executable for Windows

The game was running fine in view port but when I package it into executable and run it, this happens:

The chamfer cubes fall through landscape, but the others are still at the same location. The player took the jump and fall through landscape also.

Screen-Recording-ezgif.com-video-to-gif-converter

Have tried adjusting gravity and a number of Collision setting such as Collision Mip Level and Simple collision Mip Level but still won’t fix it. Is this a bug?

If you have resolved similar issue, please help with some instructions.

UE Version: 5.3.2

Greetings @Sapien27018228

Do the items/character have collision perimeters set? (I’d also try resetting the landscape X/Y if they do)

thanks, yes they do. I think this is caused by my floor being in a streamed level? I can create a new level instance and add to my map. But I can’t use Landscape Sculpt tool as it only works for streamed level?

How do I convert streamed level to persistent level or static mesh so I can create different terrains?

I don’t understand why but I found a workaround (not an ideal solution): when I save the map as a new level, import it into the original map, then package the project. The new level imported would work but the original map still not working …

Sorry for the late reply! Were you able to find a solution?