The restrains, do not seem to be very well defined perhaps – but one issue is the pressure load (sf) sf,all,PRES,0 applies a 0 pressure which is not what one uses as a load (zero loads), and it applies it to the sides as well as the top –
so go through the command reference (e.g., sf command) and some simple apdl examples and then try to understand what you want to do and then how to do it using apdl – I would suggest to do this in workbench, where it is much easier.
Finally go through one of our courses:
If you are not able to open the links, refer to this forum discussion: How to access the ANSYS Online Help
Hope that helps