.htaccess not writable but I set it to be writable via FTP

I am using godaddy deluxe linux server. I have more than one wordpress installation on this hosting account. The primary address for the hosting account is https://www.thetechtalkblog.com located /blog/tech, a secondary address is https://www.thegroovyagent.com located /blog/groovy. The index.php & .htaccess files for tech talk are in the root directory / and the index.php & .htaccess files for groovy are in /blog/groovy .

The problem is that wordpress can edit the .htaccess file for tech talk but not for groovy. I can manually edit the .htaccess file for groovy but I want wordpress to do the work for me. I have set the .htaccess file to 666, 755, 766 but nothing works.