According to the following sources, Lizzo has been playing the silver Muramatsu EX "Sasha Flute" since high school, besides the later addition "Blue Ivy". Sasha Flute has its own Instagram account.

Instagram, @lizzobeeating, November 12, 2018

Okay, so I just saw there are people who are, you know, doubting that I'm a classically trained flutist, all these videos are fake, we got people doubtin' me. Back when I was an artist that had like "Batches & Cookies" or whatever, they didn't give a shit what I was doing or what I was actually talented at. And I just really think that's really a sign that I'm finally poppin'!

I'mna celebrate by putting my flute together and actually blowing notes out of it, so you hoes can... shut the fuck up. This is Sasha Flute. This is an open-hole C flute, a Muramatsu, look at the B foot. 'Wow, she knows a lot about flutes! Guess she didn't study it in college.'

And now, I'm gonna play my favorite note in the entire scale, F. [plays F#] Fuck y'all!

Instagram, @sashabefluting, February 13, 2019

THAT LOW OCTAVE C & B AINT NO JOKEEEE! Last minute Sasha addition to the album ho! Lizzo let me flex, I think y’all gon love it. #flootgang

Minnesota Monthly, "Q+A: For the Love of Lizzo", April 18, 2019

Introduce us to Sasha Flute.

She’s a Muramatsu flute, which is Japanese. I’ve had this flute since my senior year of high school. It was my college flute. She’s really special. I had a marching flute, but I was really broke in Houston and had to pawn it for money. I would never pawn Sasha Flute. I guarded her with my life. Sleeping with her tucked underneath the seat of my car, just making sure that she wouldn’t get stolen. There’s a lot of love in that flute. Sometimes people are like, “Well, we’ll just rent a flute and you can play it.” I’m like, “No, it’s not going to sound the same or feel the same.” There’s an energy and a timbre that every musician has with their instrument. Sasha Flute definitely has it.

The Today Show, "Lizzo reacts to Hillary Clinton’s tweet to her", August 23, 2019 @ 3:27

Sheinelle Jones: Can we bring on, is it Blue Ivy? Is that the name of your new flute?

Lizzo: This is Sasha Flute's cousin, Blue Ivy. She's a blue custom Muramatsu flute.

Jones: Is this like some gazillion dollar flute?

Lizzo: It's the best in the game. Well, in my opinion! In my humble—'Cause Sasha is a silver Muramatsu, so, she's the blue one. You know, Sasha's on vacation. She's been working very hard. She has over two thousand followers on Instagram. She needs to get verified. Can y'all help me with that? And so she sent her cousin out, 'cause she tired of me.

Jones: Do you see it and you want to go? You just wanna—

Lizzo: Yeah, every time I pick up my flute I just hit, like, "The Flight of the Bumblebee".

Vogue, "Lizzo on Hope, Justice, and the Election", September 24, 2020

(Lizzo’s now-famous flute is known affectionately as Sasha, after Beyoncé’s alter ego, Sasha Fierce, and resides in a Swarovski-crystal case in her home.)

Netflix Is a A Joke, "My Next Guest Needs No Introduction with David Letterman | Lizzo and Letterman play the flute", October 16, 2020

Lizzo: Um, I have so many flutes! I want you to try one that's not so expensive. Oh, we can get Blue Ivy! This is Blue Ivy. She's controversial.

David Letterman: Because of the color?

Lizzo: Yeah. They were like, 'That's not a flute, it's a toy!' So, um...

Nicki Swift, "Here's How Lizzo Got Started Playing The Flute", October 24, 2020, which covers the Netflix episode

The "Juice" singer explained how, at one time in her life, her flute, which she calls Sasha Flute, was her most expensive possession. "I guarded the flute with my life," Lizzo told Letterman. She went on to formally introduce the former late-night talk show host to Sasha, a Muramatsu flute, made in Tokorozawa, Japan. She shared how her late father got her the rare flute as a gift when she was in high school.

Instagram, @sashabefluting, May 14, 2021

Gettin sperimental on tha track yall ! Lizzo had me LOCKED UP for months and I said bih if u don’t put me on the album ima shove my bfoot so far up yo ass you’ll never twerk again w out hearin flight of the bumblebee tumble out ya booty cheeks 🤬😤😾🖕🏾😡 and she said ok 😜😎🤩🎙

Instagram, @sashabefluting, April 19, 2022

Bitch.. I took a hiatus. I been BUSY— I need me a social media manager… honey I’m home! Y’all listen to MY song feat Lizzie? ‘About Damn Time’???

I remember the day I wrote this song… I just knew ‘doot doot doot doot doo doot doo doo doot’ was the song of the summer— then Lizzie added her nonsensical lyrics.. bad bitch o’clock… I guess(?)…

ANYWAYS STREAM ABOUT DAMN TIME