You can post a bug report through a DM to Bug Support if you cannot post to Bug Reports directly.
This looks like it might be a Hyperion (Roblox’s anticheat) -related bug if there’s no consistency (i.e. it happens to you regardless of the game you join), you can find more information on them, some things you can try to fix it and how to get crash dumps if you need them (for example if Staff asks for them) here: