`deno task dev` not working because `--watch` doesn't detect changes

I've run

deno task dev

deno task dev

deno task dev

deno task dev on a new project from

deno init

deno init

deno init

deno init and so it should be running the task

deno run --watch main.ts

deno run --watch main.ts

deno run --watch main.ts

deno run --watch main.ts . But when I change

main.ts

main.ts

main.ts

main.ts the command does not re-run. The output remains statically:

deno task dev
Watcher File change detected! Restarting!
Add 2 + 3 = 5
Watcher Process finished. Restarting on file change...

deno task dev
Watcher File change detected! Restarting!
Add 2 + 3 = 5
Watcher Process finished. Restarting on file change...

deno task dev
Watcher File change detected! Restarting!
Add 2 + 3 = 5
Watcher Process finished. Restarting on file change...

deno task dev
Watcher File change detected! Restarting!
Add 2 + 3 = 5
Watcher Process finished. Restarting on file change...

What am I doing wrong? I'm using Deno 2.0.4, Warp as my terminal, and zsh as my shell. I'm on macOS 14.2.1. Is this a bug?