Hey @geneviève-besseiche, sorry for the late answer.
Indeed you need to create the tags first in the tag section. It's the current way it's working.
I'll add this to our suggestions list
can you check the mobile visibility setting at all levels? (element, column, row, section)
Also Pierre's advice is correct, instead of using a logo element (which is reserved for the logo of your website), try to use images (responsive or contained) instead
