Hi Liza,
Display of buttons may be affected by authorizations. Sometimes, it is grayed-out and sometimes it is hidden. The display of buttons is usually judged in the view's implementation class. It is usually done in method do_prepare_output, or do_*button* something like this, or some interface~get_buttons. You may then debug for the system logic why the button is hidden.
Another option is that, you may trace authorization in ST01 to find out what auth object fails. Then you may test if it is really caused by check failure of this auth object.
If you are not cable of above analysis, like Kapil said, you may tell us what button is hidden in screenshot, and provide the F2 component information of this button and we will be able to check it for you.
Spencer