Sometimes, when you first apply 3Dseller's Store Designer, a part of your old eBay Store theme will still be there.
To hide this extra header, change this quick setting in your eBay account:
Step 1 - Go to Manage me Store
Navigate to My eBay > Account > Manage My Store
Step 2 - Find Display Settings:
In the left sidebar, choose “Display Settings”
Step 3 - Select Change Theme
Find the “Theme and Display” section then click “change to another theme”
Step 4 - Change your theme
In the far-left Theme menu, choose the “Easily Customizable.”
Then click “custom header only” and save.
Visit your store and your header should now be removed.
If it's still there, please try using CTRL+F5 on while viewing your store to do an advanced refresh.
If you have any questions, feel free to reach out to us anytime at firstname.lastname@example.org