Once the import starts, the gauge below will be filled. If the import is completed normally, it will become 100%.
There might be sometime this gauge stops with a certain numeral.
This happens because the upload size which is set up in your site is low.
You should increase the upload size after consulting your server on this issue.
How to increase memory and uploading size: https://whatswp.com/how-to-increase-wordpress-upload-limit/
1. Deactivate Visual Composer plugin during import demo data. few servers are not importing visual composer (5.0+)
2. If it doesn’t still import, you can try to import XML files directly.