Same issue here. I seems random when it does happen.
Also as of the most recent (update?) 1/5/2018 the spyglass change. Now when I have the spy glass equiped and go to the menu for options, the cursor disappears and I cant select anything and I have to force log out and wait the 10 mins
I remember why I stopped playing this game a year ago, the bugs make it unplayable at times and just doesnt make it worth it.