Mapped domain redirects to original domain

I installed the plugin on the original domain:

https://medicacampestre.com

I want the domain https://centrocardiovascularmc.com/ to open the page https://medicacampestre.com/centro_cardivascular but as a landing page, not a redirection, I want centrocardiovascularmc.com to remain in the address bar.

I don’t know what I’m doing wrong. I don’t see any redirection in the htaccess.

I’m hosting on siteground which doesn’t use cpanel, I don’t know if you have encountered any problems with that.

Thank you.

Pablo T.

The page I need help with: [log in to see the link]