Why does my project say 403 Forbidden?

https://super-counter.glitch.me/ says “403 Forbidden”
It was working just fine, but after I refreshed it a few times it just started saying this.

I believe you were rate limited - in that your project received too many requests in a short period of time. If you find this happening a lot, you may want to consider subscribing to Glitch Pro which removes the rate limit from your projects.