Same, i went to "Offers" in the tabs along the top and clicked Accept, and it says that I've accepted it.
If you onto "Study Plans" there's like a few more things it asks you to confirm.
Also, if you go to my.unimelb and click the "Trouble logging in?" Enter in your Student ID, Name, DOB and postcode, it will let you log in.
Mod Edit: Posts merged, please do not double post unless there is a genuine reason for doing so.