Hi I have tried on several times to change the background image on this section, but it always shows the default image. I have even tried the same image that has worked in the section above but it does not work.
Adding an updated theme will not lose any of your content, you can save the XML file of all the contents of your website for security. You can add theme through WP Dashboard.
To export xml file: you have to go to Dashboard –> Tools –> Export –> Click on download export file
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