failed to load content css

Hi

I am web designer and developer

for one of my site i use wordpress 4.8.3.
in developing mode(in local system) all admin system is working perfect
after uploading on live it is displaying error like below in admin

Failed to load content css: https://mydomain/subtheme/wp-includes/js/tinymce/skins/wordpress/wp-content.css?ver=4.8.3

i place my project in my main site folder

Thanks
Farhan

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