From my experience, even if you started transitioning in early childhood, there are always going to be a few who either want to make a point or simply don't realise what they are doing.
As you go on through the decades two things happen, or at least they did to me, 1. 98% get it right 98% of the time. and 2. you become a lot more secure in yourself so the 2% which don't get it right can be laughed off or sometimes not even noticed.
I can honestly say that at this point I no longer care. As long as people are pleasant and don't do silly things like asking me to use the wrong public toilet, or anything gender specific like that, then they can call me what they darn well like.
The odd thing is, as I think I have admitted in another thread, I've even uninetentionally slipped up ocassionally myself, and oddly enough not even always with someone who was trans. So I do wonder if this is not partly just something that everyone does from time to time and it's only because we have a particular axe to grind that we notice and get upset.
I would also say that, again from my own direct experience, it's only the passage of time that seems to make the difference. Moving away might work for a while, but unless you are going to ditch all your past friends and relatives 100%, which to me seems like a really bad idea, and a jolly good way to become very isolated, then you have to accept that news eventually travels.
I know of two people, here in the UK, who repeatedly tried to run away from their past by moving on. Both are now dead, suicides, because they found out the hard way that however far they ran the past eventually catches up. So I really wouldn't recommend that course of action.