wordpress – Banner not compatible with Google Display

I implements tags in a site in wordpress and using the plugin Announcement Builder and it turns out that the banners in 728px do not match the width of the mobile. I leave a tag as an example below:

In mobile, it keeps the width of 728 and generates a scroll to the horizontal of the site.

I can not find a way to adjust it because, after what I've seen, this tag creates one that has a style in the tag with dimensions.

The truth is the first time I'm working on the implementation of ads. If you could help me, I would appreciate it.

The question is whether this should not be solved by the client that generates the tags and sends them to me to implement them.