Also check if everything is ok in your side, I checked in: https://www.isitdownrightnow.com/alcaldia.xyz.html
A website to detect down sites, and currently the server you use is down. Please check it and if it´s still displaying that banner, please re-report this.
If you are using a free host, maybe there are in maintenance, it should be resolved in a couple of hours. Anyway check first with your host service provider. The only thing i see strange is that the site, even it has a 503 error is displaying. Maybe is something with chromium core like i said, but just make sure everything is okey on your side.
Edit: checking a little bit more in firefox:
The red numbers (error 503) indicates something is going wrong on server side, so my theory of something related with chromium core is discarted.
An error 503 usuarlly means that the site is overloded on visitors and it´s refusing more petitions. That or a mantainence from your host provider. In any case this is something you need to talk with your service provider, maybe you need an upgrade of some kind.