Hello,
Sorry for the inconvenience. If you want to resize your logo size then you need to add some CSS on your dashboard/child theme.
So go to your Dashboard > Appearance > Customize > Additional CSS.
.site-branding img.custom-logo.wp-post-image {
max-width: 420px;
}
Copy this CSS code and follow my screenshots below.
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3. 
Thank you.
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This reply was modified 2 years, 3 months ago by
WP Team.