Too high of a dose for Metformin?

18F taking Escitalopram 20mg, Mirtazapine 7.5mg, and Metformin 500mg

I was diagnosed insulin resistant a few months back and was put on Metformin for it. And some kind of vitamin but I can’t remember what. My doctor wants me to lose weight to hopefully ‘reverse the insulin resistance’ as she worded it. I’m at risk for type 2 diabetes and it runs on both sides of the family. As I’ve been having problems losing weight she recommended I take GLP-1 to help. I very much can’t afford it and haven’t found any other solutions yet. Fast forward a little I’m out with a friend and her mom(doctor) who casually mentions that for someone who’s insulin resistant 500mg is too low of a dose. No idea how she found out the dose, I’m guessing she saw the medication in my purse. She’s not my doctor so I’m not going to automatically follow her advice, but she says I should be on 1700 to 2000mg. That seems very high and like a huge change. Should I mention this to my doctor? I don’t think it’s worth mentioning, but it definitely caught my attention. I have no medical knowledge whatsoever so I was hoping to get another perspective on this.