My header ad is not working

Hi there,

the header widget is set to only fill 50% of the space available.
You can change that with this CSS:

.header-widget {
    max-width: 100%;
}

There is one more problem after implementing css code. The site title and tag comin in the same line with the advertisement. I want an advertisement below the title of site

It may be better to use the generate_after_header_content hook for your ad: https://docs.generatepress.com/article/hooks-element-overview/

If you want to use the Header Widget, try adding this CSS:

.inside-header {
    display: flex;
    flex-direction: column;
}

.header-widget {
    order: 10;
}

It is helpful but I have one more question. How can I hide the top bar widget in the desktop and show it on mobile? Please help

try this CSS:

@media(min-width: 769px) {
    .top-bar {
        display: none;
    }
}

Thank you so much

You're welcome