you need to have line of sight!
oh! I just re-read your description! that is my fault for not reading everything ( even though you clearly placed it in BOLD LETTERS and is the first thing to read!) omg that is 100 percent my fault, I'm blind and Dumb...I am so sorry.
I treated this as a thing where you can switch wherever you are, no matter the distance. then I got no complaints then! solid game I changed your rating, AGAIN IM DUMB FOR MISSING THAT....