Hello, this is a common thing probably.
When cesium runs, and im flying around my scene, even in a packed project, I can see the tiles loading, for example when i turn around with the camera the tiles around appears and disappear.
Is there any way to make at least the loaded tiles still? So do not refresh them around the camera or scene?
In your tileset, do you have the “Enable Frustum Culling” setting checked? If so, I would turn that setting off, so that tiles outside of the camera view do not get culled.
But if you still have that problem even with the setting disabled, let us know! It would help to have a screenshot of your Cesium3DTileset’s settings so we can further troubleshoot. Thank you!