Seems like rewrite directives are not enabled on your server. Please try to upload attached .htaccess file to your server root directory. Then try to check if that was helpful.
Some hosting providers do not allow to upload .htaccess files on their servers and block them so in that case you need contact your hosting provider asking them to enable mod_rewrite and the directives stored in attached .htaccess file.
Contact us if you have any additional questions!