Header Slide problem

I just boguth Sydney pro and install into my wordpresss, and also following the instrction

  1. when I click import demo, there are fail error massage like " [ERROR] Failed to import “sample_products.csv” "

2, in header siler, and I typed in tiltle and upload new images, but there are no change at all as below pic
I struggling 2 days for this problem, what am I missing ? and what should I do ?

Do use WooCommerce on your site? If don’t, this error message is not a problem. You can ignore it.

Do you have active caching on your site? If so, please flush it and reload your site.

aThemes Support