My (M30) MIL (F65) Constantly Calls Me by the Incorrect Name. How do I get her to stop?

I (M30) have been married to my wife (F35) for a couple years. I have always wanted a good relationship with my in-laws, and things have generally been really good. Aside from a few minor things here and there, things have been great. There is one sticking point though.

I have a name that is often misheard, and it's caused me some minor annoyance my entire life. For the purpose of this post, my name is Andy. When I first met my future MIL, my then girlfriend said: "this is my boyfriend, Andy." "Nice to meet you, Randy!" future MIL responds. I'm not super quick to correct her since I'm really non-confrontational and I really want to get on her good side. Over the next few weeks, she continues to call me Randy, and my then girlfriend and I correct her a few times.

Things start to get a little out of hand when I go on a trip with my then girlfriend to visit her family living abroad. My MIL introduces me to everyone as "Randy," and I have to try and make the rounds and correct my name for the record. Regardless, a few of her family members keep calling me "Randy" among the confusion.

Years later, we're happily married and starting our life together. We've since ensured everyone in her family knows my actual name, and aside from the occasional nickname, everyone is calling me by my actual name. That is, except for my MIL. Every time we have an interaction, she calls me "Randy." She has even done this in front of my parents and family, which has caused some eyebrow raising. My wife and her siblings also correct her whenever she calls me the wrong name, but she just ignores them.

I'm kinda not sure what to do at this point. It was a little awkward and annoying having my girlfriend's mom call me the wrong name, but having my MIL purposely call me the wrong name feels insulting. I'm sure she sees it as a fun inside joke, but I'm really not happy constantly being called the wrong name. I would have a heart to heart with her, but it's not her communication style to have those kinds of conversations. Even if it was, I'm certain it wouldn't change anything.

Short of assuming a new identity, how do I get her to stop calling me Randy?