Just some outsider observations made over the years - take them or leave them as you wish:
Most people don't seem to get upset when they are called by the wrong title unless they are Doctors, primary teachers or university professors. Try not to be too sensitive to it. People make mistakes. Just try to have a chuckle at their expense (they are the one making the mistake after all) and move on. Don't take it too personally if it comes once from someone who works minimum wage - they are probably just counting the minutes until they are off the clock anyways.
I've noticed when you start to push it folks become defensive and will try and pick out a few traits to throw at you. However if you just smile at them as if asking "did you just call me?" they will generally get embarrassed and then: not say anything! Just
in case you missed the slip-up.
I was born male and present male still and I've been ma'am'ed several times by cashiers. What it boils down to is that they aren't paying attention and say just what they are in the habit of saying.
At a restaurant - allow the server one mistake. It's when they do it a second time that it's no longer accidental - unless they cringe and/or try to correct themselves - you need to say something.
Hell even I've make this mistake! At the end of a double shift I called a big black woman sir realized my mistake and apologized. Luckily she laughed and asked if her new hair cut was really that bad (it was - but that's a story for another time).
Hope something in here helps.
