IFTTT is going to need access to your xmlrpc.php file in order to run, but that’s blocked: https://etesco.com.br/xmlrpc.php
Unfortunately, blocking XML-RPC is not a great solution for fighting security risks. It’s akin to selling your car because you don’t want it to be stolen.
Your site’s XML-RPC file is kind of like a communication gateway to your site. The WordPress Mobile Apps, and many plugins and services will use this file to communicate to your site. If this is blocked, you will have other issues pop-up down the road for the same reasons.
If you are using any security plugins, please try connecting with those temporarily deactivated. If you don’t have any, or if that didn’t work, I would suggest contacting your hosting provider and asking them to unblock your site’s XML-RPC. The most popular hosting providers out there have managed to find other ways to protect their servers without having to hinder your site and your ability to use services with your WordPress site.