Empty image in protfolio slider not delete.

Hello,

Sometimes, when I want to delete image from slider in protfolio, the image not delete.
also, when i upload image, the image doesnt visible good. just after refresh the page, the image visible good.
I need your help.
thank you.

liran.

http://ergotech.anova-host.com/wp-content/uploads/2016/12/problemimage.jpeg

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