There can be a few ways to solve this:
1.) If you have “JetPack” plugin installed and activated, try deactivating it first before uploading and installing the theme.
2.) Some web hosts have very limited “Maximum Upload Size” set in its “php.ini” settings file. The “morphis.zip” file has a file size of 9MB+. Contact your hosting provider as to how you can increase its “Maximum Upload Size”.
3.) Lastly, try unzipping first “morphis.zip” file and upload its resulting folder through FTP in ”/wp-content/themes/” folder.