Did somehow a great logo in the header of the forum phpBB and of course the name of the site and the description was imposed on it and prevented.
To hide the site name and description in the directory of the active theme (style), find the file /style/stylename/template/overall_header.html
Open it in a text editor and find the following two lines in it:
<h1>{SITENAME}</h1>
<p>{SITE_DESCRIPTION}</p>
Just they are responsible for displaying the site name and description in the forum header, we will not delete them, they will come in handy, but simply comment:
<!-- <h1>{SITENAME}</h1>
<p>{SITE_DESCRIPTION}</p> -->
After that, clear the forum cache by clicking the button in the administrator’s pane.
Done.