Unfortunately, the domain renewal is not included with renewal of your hosting service.

This is not included because the domain name itself and the hosting for your site are two different services, the hosting with us is  for the hosting of your site and emails whereas the domain name is simply the address for your site. These services themselves are completely separate as far as billing is concerned. However your domain name and hosting with us can be renewed at the same time within the same invoice, but the renewal of each service does not generally affect the other.