I would hope the error would be resolved as soon as possible but I’ll say your site should most definitely be back online within 24 hours, they might be performing critical maintenance or essential upgrades to ensure your website performs better and users experience better services, they might be migrating mass accounts etc, so hopefully your site comes back online they might have chosen today as they didn’t think many would be trying to access sites etc as a holiday I can only assume.
Yeah that is another error for 000webhost technical staff to correct, it must be set to the previous domain that would appear when you edit your site i.e kadirdemirel.net84.net or whatever would appear.