Why can’t I see all my contacts on my PSP Contacts List?
Unfortunately, the PSP can only display 150 contacts at a time. If you have more than 150 contacts on your Contact List, they won’t all be displayed.
You could try setting up a second Skype account for your PSP and add only your favourite contacts. This way, your favourite contacts won’t be left off your contact list when you sign in to Skype on your PSP.
Find out how to set up a new Skype account on your PSP