Error loading new Themes

Seeking advice: we are unable to upload any new themes to our WordPress site. It doesn’t appear to be any one theme, as we have tried a half-dozen with the same results. The error message looks like this:

Installing Theme from uploaded file: moesia.1.13.zip
Unpacking the package…

Installing the theme…

Could not create directory. /home/content/83/11133283/html/wp-content/themes/moesia/

Theme install failed.

We have tried downloading the zip file right from the creators websites.
We have never had this issue before.

Next steps? Thanks!
Brian