Major problem top menu duplicate the URL (new tab and current)

Have a good day.

I’m a spanish user please forgive my grammar.

I have created a WordPress site, installed the theme Sparkling.

First time when I finished of customize the blog, I found a big problem:

When I click any link on top, the target url opens in same window and new tab.

Then readers will left the blog without even read any article, because I have some important links there.

My website URL is:
https://www.cdci.com.co/blog

After I noticed the problem I erased the folder in FTP and deleted the BD and started over again… but I readed a lot, seems like problem is part of Template… I disabled all plugins at tried as much as I could… still have no clue.

I appreciatte deeply any help, because my companies project depends from this.

Thank for your help,
Chanag.