Halsey at last delivered her third studio album, Manic, on Friday (Jan. 17), and “3am” was the track that caught fans’ attention, especially the voicemail at the end.

When a fan on Twitter asked if the male voice was her father’s, Halsey clarified that the sweet message was actually left by her fellow musician pal, John Mayer, discussing the songstress’ Hot 100 chart topper, “Without Me.”

“He predicted the success of without me before I had faith in myself,” she wrote. In the voicemail, Mayer is heard praising, “Your best song is the song that’s currently on the radio. How many people can say that? That their best song was the one that’s currently about to be a massive hit. It’s already a hit.”

“It’s just gonna get more massive. How many people can say it? Not very many. Congratulations!” he concludes, which is a fitting reassurance, given that “3am” details Halsey’s insecurities after a night of drinking.

She also responded to a follow-up question wondering if the song was actually written at 3 a.m., which she revealed that it was. “After a night out where I came home and was ringing everyone in my contacts cause I was dying to talk to literally ANYONE so I wouldn’t have to sit with my own thoughts,” she explained. “I realized ‘hmm this is…bad.’ and wrote a song about it!”