First of all, gotta see ur position...
Senior position takes longer to get promoted, but since you are
a fresh grad, I presume you are holding entry position.
For Job Title Change, got to see your job position. For example,
if you are "Accountant" (not account asst), some company/department
might not have a "Senior Accountant" position, thus, you are not
able to go on job title change.
Another reason is that there is no position availiable, ie: no
one above got promoted or left company or no new estab. Thus
no vacany.
And if the ppl who get job title change are in the same dept and
doing the same thing as you, then something must be wrong. Approach
your reporting officer (or boss) in a non-hostile way for a 1-to-1
chat. It might be that you are not performing as well as ur peers
or something goes wrong somewhere.