Need Help Deleting Second Header

Hi Everyone, I am new to Contao. I work at an elementary school and was given the job of updating our school Web site. I have had two hours of training. I have figured out enough to get pertinent information on the site. However, my assistant principal added some information to the site and now we have two headers. I don't know what she did and she doesn't know what she did. On some of the pages the slideshow is the same. On other pages it's show two different slideshows. I have attached an image. Can anyone tell me how to get rid of the second header?

Go to Layout - Themes, klick on third icon to the right (Edit the page layouts), klick on Edit on your page layout and check if you have several identical entries for "Header" under Front end modules. Repeat the process for any other layout.