In March 2018, Shawn’s single “In My Blood” was released and quickly became a sort of anxiety anthem, with his mental health being the center of the song. In an interview with Beat 1’s Zane Lowe, Shawn revealed that “In My Blood” was the first song he wrote off that album.
“Every time I play that song for someone I got, ‘Just so you know, I’m okay.'”
The song is about Shawn’s struggles with anxiety and was born from a desire to be fully transparent about what it felt like for him.
Source: https://www.distractify.com/p/why-did-shawn-mendes-cancel-his-tour