The talent manager — who reps Miller’s ex-girlfriend Ariana Grande as well as Justin Bieber, Carly Rae Jepsen, Dan + Shay, Tori Kelly and more — posted a touching tribute to Miller on Instagram Saturday.
“This was a good man with a great heart,” he wrote of a photo of Miller. “He will be missed and is gone way too soon. I’m angry to say RIP buddy.”
“Always a kind heart,” Braun, 37, added. “You will be missed and you are gone way too soon. Way too soon. Rest In Peace Mac.”
Miller, whose real name was Malcolm McCormick, was pronounced dead at 11:51 a.m. at his Studio City, California, home on Friday, the Los Angeles County Department of Medical Examiner-Coroner confirmed in a statement to PEOPLE. He was 26.
A cause of death is yet to be determined, but a source told PEOPLE that Miller had gone into cardiac arrest after appearing to suffer a drug overdose.
Grande and Miller split in May after two years dating. She is currently engaged to Pete Davidson.
The “No Tears Left to Cry” singer, 25, has not spoken out about her ex’s death, but some online trolls blamed her for his dead on Instagram, and Grande shut her comments off in response.
Throughout his life, Miller was very open about his struggles with drugs and sobriety. Following his Macadelic tour in 2012 and the release of his first studio album Blue Slide Park, Miller admitted he turned to drugs to cope with stress.
“I love lean; it’s great… I was not happy and I was on lean very heavy,” Miller told Complex in 2013. “I was so f—ed up all the time it was bad. My friends couldn’t even look at me the same. I was lost.”
While Miller attempted to turn his life around within the past couple of years, he was arrested for DUI in May.
Last month he told Rolling Stone he doesn’t classify himself as a drug addict. “If a bunch of people think I am a huge drug addict, Okay. Cool,” he said. “What can I really do? Go talk to all those people and be like ‘Naw man, it’s really not that simple?’ Have I done drugs? Yeah. But am I a drug addict? No.”
Though Miller and Grande’s split in May came as a shock to many, both remained respectful after their breakup. Grande even dedicated an Instagram Story to the rapper in which she called him “one of my best friends in the whole world and favorite people on the planet.”
“I respect and adore him endlessly and am grateful to have him in my life in any form, at all times regardless of how our relationship changes or what the universe holds for each of us!” the singer wrote.
Miller also opened up about the split during a conversation with Zane Lowe on Beats 1 on Apple Music in July, explaining that both he and Grande had moved on since their split. “I was in love with somebody. We were together for two years. We worked through good times, bad times, stress and everything else. And then it came to an end and we both moved on. And it’s that simple,” he said.
“It’s all positive energy,” he added. “I am happy for her and [the fact that she’s] moving forward with her life, just as I’m sure she is with me.”
If you or someone you know is in need of help, please contact the SAMHSA substance abuse helpline at 1-800-662-HELP.