When I invited a Player to My World when He joined & Telling me where am I & I told him I'm at spawn but He does NOT see me & when I place & break blocks around him he can't see blocks breaking or placed & when I told him to walk over the (small tunnel) Cave entrance (That I covered with snow) but when he goes exiting the entrance he walks through the snow blocks & when I mine the blocks where the player is standing & then he floats (While NOT flying in creative) But then any Minute he notices that I'm standing & Glitching my character fast (The spot I last stand/fly a minute ago) & I was in the bottom hole but he thinks I was moving everywhere fast where I was last standing (since a minute ago) but he knows I wasn't. But a Few Minutes he now notices that the blocks covered in the small cave tunnel are placed by me and the spot blown up by me.

But I'm NOT sure if this was just a bug or the Internet doing this & NOT sure if anyone had reported this bug because I couldn't find it.