My understanding is that a lot of things can affect ALT and AST. About a year ago I had a super high elevated ALT (without having used any AAS) and it took me a lot of work, changing my diet and adding NAC, to bring it back to the reference range. I got an ultrasound after a few months of slow progress (before I made the changes that got me good results) and was diagnosed with NAFLD. I also don't drink.
I also believe that orals in general cause this, anavar being one of those routine offenders for those that it decides to mess with. Since you stopped anavar 3 weeks ago it may just be a question of time, but if you have NAFLD (as in, if you get your liver imaged and they say it's bigger than they would expect) you can make some changes to your diet that could potentially make a big difference. Feel free to DM me if you'd like a list of the changes I made to mine.
And if you have been taking orals without NAC: it's time to start taking NAC. My ALT is back in the range and I'm still taking mine.
There are better bro's on here who can give better advice than mine, but I hope I've helped a little.