Why am I getting 503 responses when Uptime Robot pings my project?

I’ve been trying to mess around for a while now, and this is the current state of my responses on Uptime Robot: the image

Apparently, the bot itself I’m hosting is up and is working perfectly fine, even waited 5 minutes to check that, perfectly fine. I saw that a staff member was available to review the code and respond with what’s wrong so I’ll greatly appreciate that if a staff member could do that for me.
getting a little desperate here now
Project: https://building-a-real-bomb.glitch.me/

Your project is private so cannot be viewed. Either make it public or DM me a join link so that I can take a look. Thanks.