I don't have screenshots but I think I've figured out how to obtain this bug.
While my char is running helper on spot, if I open warp menu and select map what I need helper closes and whoa, we've got teleport bug. Our char is stuck in map and only switch char/serv can help us.
Before I've pass 4th class quest I didn't had this issue even when I teleport char to other man while helper was running.
Maybe it would help but anyway I'll take screenshot when my char again will have this crap
upd:
Bug time : 22:34