Did they give you root password?Oke so my Hosting has confirmed that I do indeed have full root access. So it seems that's there is a step I am missing here.
If not it's possibe that the username you got is in sudoers group, and in that case you can set password for root like this:
sudo passwd root
you will be prompted to give the new root password 2 times.
After that you can become root like this:
su -
give the root password and you are the root user.