I think it has something do to with them being unanchored, because when you have an anchored part that moves through scripting, your character just stays on it.
I don’t really know of any fixes for this.
Try making sure those strings are like actual strings so they can move and make sure that the actual part is unanchored. If it’s anchored it won’t move.
You can make a simple whitelist system using the IgnoreTag in one of the client scripts, I can make a demo when I get the chance to see the script again.